Search Results

Search found 22277 results on 892 pages for 'multiple addresses'.

Page 314/892 | < Previous Page | 310 311 312 313 314 315 316 317 318 319 320 321  | Next Page >

• User Productivity Kit - Powerful Packages (Part 2)

  - by [email protected]

  In my first post on packages I described what a package is and how it can be used. I also started explaining some of the considerations that should be taken into account when determining how to arrange your packages. The first is when the files are interrelated and depend on one another such as an HTML file and it's graphics. A second consideration is how the files are used in your outlines. Let's say you're using a dozen Word doc files. You could place them all in a single package or put each Word doc file in a separate package but what's the right thing to do? There are several factors that will influence your decision. To understand the first, let me explain a function of UPK publishing. Take an outline in UPK that has an attachment (concept, frame link, or hyperlink) that points to a file in a package. When you publish this outline, the publishing engine will determine that there is a link to a file in the package and copy the contents of the package to the publishing destination directory. This is done to ensure that any interrelated files are kept together. For the situation where you have an HTML file with links to number of graphics files, this is a good thing. If, however, the package has a dozen unrelated Word doc files and you link to only one of them, all dozen Word documents will be copied to the publishing destination directory.  Whether or not this is a good thing is dependent on two things. First, are all of the files in the package used in the outline that you're publishing? Take an outline that includes links to all of the Word documents in that dozen document package I described earlier. For this situation, you may choose to keep all the files in a single package for convenience. A second consideration is how your organization leverages reuse in UPK. In this context, I'm referring to the link style of reuse such as when you link to the same topic from multiple UPK outlines and changes to the topic appear in both places. Take an example where you have the earlier mentioned dozen Word document package and an outline with a dozen topics in it. Each topic has an attachment pointing to one of the Word documents in the package (frame link, concept, etc.) If you're only publishing this outline, the single package probably works fine but what if you're reusing one of these topics in another outline? As I explained earlier, linking to one file in the package will result in all files in the package being copied to your published output. In this example, linking to one topic in the first outline will result in all dozen Word documents being copied to the published output. This may result in files in the output that you don't want there for business or size reasons. This is a situation in which you should consider placing each of the Word documents in it's own separate package. With each document in it's own package, that link to a single document will result in only that single package and single Word document being copied to the published output. In my last post I had described that packages are documents in the UPK library. When using the multi-user version of the UPK Developer you can leverage standard library capabilities for managing the files in these packages during the development process - capabilities such as check in / check out, history, etc. When structuring your packages take into consideration how the authors are going to be adding, modifying and deleting files from the packages. A single package is a single document in the UPK library. Like any other document in the library, a single user can check out the package and edit it at a time. If you have a large number of files in a single package and these must be modified by many users, you need to consider whether this will cause problems as multiple users compete to update the same package. If the files don't depend on each other consider placing the files in separate packages to reduce contention. I hope you've enjoyed these two posts on how you can leverage the power of packages in your content. In summary, consider the following when structuring your packages: Is the asset a single, standalone file or a set of files that depend on each other? Will all the files always be used together in a single outline or may only some of the files be needed based on how the content is reused across multiple outlines? Will multiple developers need to update the files in a single package or should you break it into multiple packages to reduce contention when checking out the document? We'd like to hear from you on how you're using packages in your content. Please add your comments below! Thank you and I hope these two posts have given you additional insights into how to use packages in your content and structure them for efficient use. John Zaums Senior Director, Product Development Oracle User Productivity Kit

  Read the article

• Availability Best Practices on Oracle VM Server for SPARC

  - by jsavit

  This is the first of a series of blog posts on configuring Oracle VM Server for SPARC (also called Logical Domains) for availability. This series will show how to how to plan for availability, improve serviceability, avoid single points of failure, and provide resiliency against hardware and software failures. Availability is a broad topic that has filled entire books, so these posts will focus on aspects specifically related to Oracle VM Server for SPARC. The goal is to improve Reliability, Availability and Serviceability (RAS): An article defining RAS can be found here. Oracle VM Server for SPARC Principles for Availability Let's state some guiding principles for availability that apply to Oracle VM Server for SPARC: Avoid Single Points Of Failure (SPOFs). Systems should be configured so a component failure does not result in a loss of application service. The general method to avoid SPOFs is to provide redundancy so service can continue without interruption if a component fails. For a critical application there may be multiple levels of redundancy so multiple failures can be tolerated. Oracle VM Server for SPARC makes it possible to configure systems that avoid SPOFs. Configure for availability at a level of resource and effort consistent with business needs. Effort and resource should be consistent with business requirements. Production has different availability requirements than test/development, so it's worth expending resources to provide higher availability. Even within the category of production there may be different levels of criticality, outage tolerances, recovery and repair time requirements. Keep in mind that a simple design may be more understandable and effective than a complex design that attempts to "do everything". Design for availability at the appropriate tier or level of the platform stack. Availability can be provided in the application, in the database, or in the virtualization, hardware and network layers they depend on - or using a combination of all of them. It may not be necessary to engineer resilient virtualization for stateless web applications applications where availability is provided by a network load balancer, or for enterprise applications like Oracle Real Application Clusters (RAC) and WebLogic that provide their own resiliency. It's (often) the same architecture whether virtual or not: For example, providing resiliency against a lost device path or failing disk media is done for the same reasons and may use the same design whether in a domain or not. It's (often) the same technique whether using domains or not: Many configuration steps are the same. For example, configuring IPMP or creating a redundant ZFS pool is pretty much the same within the guest whether you're in a guest domain or not. There are configuration steps and choices for provisioning the guest with the virtual network and disk devices, which we will discuss. Sometimes it is different using domains: There are new resources to configure. Most notable is the use of alternate service domains, which provides resiliency in case of a domain failure, and also permits improved serviceability via "rolling upgrades". This is an important differentiator between Oracle VM Server for SPARC and traditional virtual machine environments where all virtual I/O is provided by a monolithic infrastructure that itself is a SPOF. Alternate service domains are widely used to provide resiliency in production logical domains environments. Some things are done via logical domains commands, and some are done in the guest: For example, with Oracle VM Server for SPARC we provide multiple network connections to the guest, and then configure network resiliency in the guest via IP Multi Pathing (IPMP) - essentially the same as for non-virtual systems. On the other hand, we configure virtual disk availability in the virtualization layer, and the guest sees an already-resilient disk without being aware of the details. These blogs will discuss configuration details like this. Live migration is not "high availability" in the sense of "continuous availability": If the server is down, then you don't live migrate from it! (A cluster or VM restart elsewhere would be used). However, live migration can be part of the RAS (Reliability, Availability, Serviceability) picture by improving Serviceability - you can move running domains off of a box before planned service or maintenance. The blog Best Practices - Live Migration on Oracle VM Server for SPARC discusses this. Topics Here are some of the topics that will be covered: Network availability using IP Multipathing and aggregates Disk path availability using virtual disks defined with multipath groups ("mpgroup") Disk media resiliency configuring for redundant disks that can tolerate media loss Multiple service domains - this is probably the most significant item and the one most specific to Oracle VM Server for SPARC. It is very widely deployed in production environments as the means to provide network and disk availability, but it can be confusing. Subsequent articles will describe why and how to configure multiple service domains. Note, for the sake of precision: an I/O domain is any domain that has a physical I/O resource (such as a PCIe bus root complex). A service domain is a domain providing virtual device services to other domains; it is almost always an I/O domain too (so it can have something to serve). Resources Here are some important links; we'll be drawing on their content in the next several articles: Oracle VM Server for SPARC Documentation Maximizing Application Reliability and Availability with SPARC T5 Servers whitepaper by Gary Combs Maximizing Application Reliability and Availability with the SPARC M5-32 Server whitepaper by Gary Combs Summary Oracle VM Server for SPARC offers features that can be used to provide highly-available environments. This and the following blog entries will describe how to plan and deploy them.

  Read the article

• "Imprinting" as a language feature?

  - by MKO

  Idea I had this idea for a language feature that I think would be useful, does anyone know of a language that implements something like this? The idea is that besides inheritance a class can also use something called "imprinting" (for lack of better term). A class can imprint one or several (non-abstract) classes. When a class imprints another class it gets all it's properties and all it's methods. It's like the class storing an instance of the imprinted class and redirecting it's methods/properties to it. A class that imprints another class therefore by definition also implements all it's interfaces and it's abstract class. So what's the point? Well, inheritance and polymorphism is hard to get right. Often composition gives far more flexibility. Multiple inheritance offers a slew of different problems without much benefits (IMO). I often write adapter classes (in C#) by implementing some interface and passing along the actual methods/properties to an encapsulated object. The downside to that approach is that if the interface changes the class breaks. You also you have to put in a lot of code that does nothing but pass things along to the encapsulated object. A classic example is that you have some class that implements IEnumerable or IList and contains an internal class it uses. With this technique things would be much easier Example (c#) [imprint List<Person> as peopleList] public class People : PersonBase { public void SomeMethod() { DoSomething(this.Count); //Count is from List } } //Now People can be treated as an List<Person> People people = new People(); foreach(Person person in people) { ... } peopleList is an alias/variablename (of your choice)used internally to alias the instance but can be skipped if not needed. One thing that's useful is to override an imprinted method, that could be achieved with the ordinary override syntax public override void Add(Person person) { DoSomething(); personList.Add(person); } note that the above is functional equivalent (and could be rewritten by the compiler) to: public class People : PersonBase , IList<Person> { private List<Person> personList = new List<Person>(); public override void Add(object obj) { this.personList.Add(obj) } public override int IndexOf(object obj) { return personList.IndexOf(obj) } //etc etc for each signature in the interface } only if IList changes your class will break. IList won't change but an interface that you, someone in your team, or a thirdparty has designed might just change. Also this saves you writing a whole lot of code for some interfaces/abstract classes. Caveats There's a couple of gotchas. First we, syntax must be added to call the imprinted classes's constructors from the imprinting class constructor. Also, what happends if a class imprints two classes which have the same method? In that case the compiler would detect it and force the class to define an override of that method (where you could chose if you wanted to call either imprinted class or both) So what do you think, would it be useful, any caveats? It seems it would be pretty straightforward to implement something like that in the C# language but I might be missing something :) Sidenote - Why is this different from multiple inheritance Ok, so some people have asked about this. Why is this different from multiple inheritance and why not multiple inheritance. In C# methods are either virtual or not. Say that we have ClassB who inherits from ClassA. ClassA has the methods MethodA and MethodB. ClassB overrides MethodA but not MethodB. Now say that MethodB has a call to MethodA. if MethodA is virtual it will call the implementation that ClassB has, if not it will use the base class, ClassA's MethodA and you'll end up wondering why your class doesn't work as it should. By the terminology sofar you might already confused. So what happens if ClassB inherits both from ClassA and another ClassC. I bet both programmers and compilers will be scratching their heads. The benefit of this approach IMO is that the imprinting classes are totally encapsulated and need not be designed with multiple inheritance in mind. You can basically imprint anything.

  Read the article

• What's up with LDoms: Part 4 - Virtual Networking Explained

  - by Stefan Hinker

  I'm back from my summer break (and some pressing business that kept me away from this), ready to continue with Oracle VM Server for SPARC ;-) In this article, we'll have a closer look at virtual networking.  Basic connectivity as we've seen it in the first, simple example, is easy enough.  But there are numerous options for the virtual switches and virtual network ports, which we will discuss in more detail now.   In this section, we will concentrate on virtual networking - the capabilities of virtual switches and virtual network ports - only.  Other options involving hardware assignment or redundancy will be covered in separate sections later on. There are two basic components involved in virtual networking for LDoms: Virtual switches and virtual network devices.  The virtual switch should be seen just like a real ethernet switch.  It "runs" in the service domain and moves ethernet packets back and forth.  A virtual network device is plumbed in the guest domain.  It corresponds to a physical network device in the real world.  There, you'd be plugging a cable into the network port, and plug the other end of that cable into a switch.  In the virtual world, you do the same:  You create a virtual network device for your guest and connect it to a virtual switch in a service domain.  The result works just like in the physical world, the network device sends and receives ethernet packets, and the switch does all those things ethernet switches tend to do. If you look at the reference manual of Oracle VM Server for SPARC, there are numerous options for virtual switches and network devices.  Don't be confused, it's rather straight forward, really.  Let's start with the simple case, and work our way to some more sophisticated options later on.  In many cases, you'll want to have several guests that communicate with the outside world on the same ethernet segment.  In the real world, you'd connect each of these systems to the same ethernet switch.  So, let's do the same thing in the virtual world: root@sun # ldm add-vsw net-dev=nxge2 admin-vsw primary root@sun # ldm add-vnet admin-net admin-vsw mars root@sun # ldm add-vnet admin-net admin-vsw venus We've just created a virtual switch called "admin-vsw" and connected it to the physical device nxge2.  In the physical world, we'd have powered up our ethernet switch and installed a cable between it and our big enterprise datacenter switch.  We then created a virtual network interface for each one of the two guest systems "mars" and "venus" and connected both to that virtual switch.  They can now communicate with each other and with any system reachable via nxge2.  If primary were running Solaris 10, communication with the guests would not be possible.  This is different with Solaris 11, please see the Admin Guide for details.  Note that I've given both the vswitch and the vnet devices some sensible names, something I always recommend. Unless told otherwise, the LDoms Manager software will automatically assign MAC addresses to all network elements that need one.  It will also make sure that these MAC addresses are unique and reuse MAC addresses to play nice with all those friendly DHCP servers out there.  However, if we want to do this manually, we can also do that.  (One reason might be firewall rules that work on MAC addresses.)  So let's give mars a manually assigned MAC address: root@sun # ldm set-vnet mac-addr=0:14:4f:f9:c4:13 admin-net mars Within the guest, these virtual network devices have their own device driver.  In Solaris 10, they'd appear as "vnet0".  Solaris 11 would apply it's usual vanity naming scheme.  We can configure these interfaces just like any normal interface, give it an IP-address and configure sophisticated routing rules, just like on bare metal.  In many cases, using Jumbo Frames helps increase throughput performance.  By default, these interfaces will run with the standard ethernet MTU of 1500 bytes.  To change this,  it is usually sufficient to set the desired MTU for the virtual switch.  This will automatically set the same MTU for all vnet devices attached to that switch.  Let's change the MTU size of our admin-vsw from the example above: root@sun # ldm set-vsw mtu=9000 admin-vsw primary Note that that you can set the MTU to any value between 1500 and 16000.  Of course, whatever you set needs to be supported by the physical network, too. Another very common area of network configuration is VLAN tagging. This can be a little confusing - my advise here is to be very clear on what you want, and perhaps draw a little diagram the first few times.  As always, keeping a configuration simple will help avoid errors of all kind.  Nevertheless, VLAN tagging is very usefull to consolidate different networks onto one physical cable.  And as such, this concept needs to be carried over into the virtual world.  Enough of the introduction, here's a little diagram to help in explaining how VLANs work in LDoms: Let's remember that any VLANs not explicitly tagged have the default VLAN ID of 1. In this example, we have a vswitch connected to a physical network that carries untagged traffic (VLAN ID 1) as well as VLANs 11, 22, 33 and 44.  There might also be other VLANs on the wire, but the vswitch will ignore all those packets.  We also have two vnet devices, one for mars and one for venus.  Venus will see traffic from VLANs 33 and 44 only.  For VLAN 44, venus will need to configure a tagged interface "vnet44000".  For VLAN 33, the vswitch will untag all incoming traffic for venus, so that venus will see this as "normal" or untagged ethernet traffic.  This is very useful to simplify guest configuration and also allows venus to perform Jumpstart or AI installations over this network even if the Jumpstart or AI server is connected via VLAN 33.  Mars, on the other hand, has full access to untagged traffic from the outside world, and also to VLANs 11,22 and 33, but not 44.  On the command line, we'd do this like this: root@sun # ldm add-vsw net-dev=nxge2 pvid=1 vid=11,22,33,44 admin-vsw primary root@sun # ldm add-vnet admin-net pvid=1 vid=11,22,33 admin-vsw mars root@sun # ldm add-vnet admin-net pvid=33 vid=44 admin-vsw venus Finally, I'd like to point to a neat little option that will make your live easier in all those cases where configurations tend to change over the live of a guest system.  It's the "id=<somenumber>" option available for both vswitches and vnet devices.  Normally, Solaris in the guest would enumerate network devices sequentially.  However, it has ways of remembering this initial numbering.  This is good in the physical world.  In the virtual world, whenever you unbind (aka power off and disassemble) a guest system, remove and/or add network devices and bind the system again, chances are this numbering will change.  Configuration confusion will follow suit.  To avoid this, nail down the initial numbering by assigning each vnet device it's device-id explicitly: root@sun # ldm add-vnet admin-net id=1 admin-vsw venus Please consult the Admin Guide for details on this, and how to decipher these network ids from Solaris running in the guest. Thanks for reading this far.  Links for further reading are essentially only the Admin Guide and Reference Manual and can be found above.  I hope this is useful and, as always, I welcome any comments.

  Read the article

• Windows Azure VMs - New "Stopped" VM Options Provide Cost-effective Flexibility for On-Demand Workloads

  - by KeithMayer

  Originally posted on: http://geekswithblogs.net/KeithMayer/archive/2013/06/22/windows-azure-vms---new-stopped-vm-options-provide-cost-effective.aspxDidn’t make it to TechEd this year? Don’t worry!  This month, we’ll be releasing a new article series that highlights the Best of TechEd announcements and technical information for IT Pros.  Today’s article focuses on a new, much-heralded enhancement to Windows Azure Infrastructure Services to make it more cost-effective for spinning VMs up and down on-demand on the Windows Azure cloud platform. NEW! VMs that are shutdown from the Windows Azure Management Portal will no longer continue to accumulate compute charges while stopped! Previous to this enhancement being available, the Azure platform maintained fabric resource reservations for VMs, even in a shutdown state, to ensure consistent resource availability when starting those VMs in the future.  And, this meant that VMs had to be exported and completely deprovisioned when not in use to avoid compute charges. In this article, I'll provide more details on the scenarios that this enhancement best fits, and I'll also review the new options and considerations that we now have for performing safe shutdowns of Windows Azure VMs. Which scenarios does the new enhancement best fit? Being able to easily shutdown VMs from the Windows Azure Management Portal without continued compute charges is a great enhancement for certain cloud use cases, such as: On-demand dev/test/lab environments - Freely start and stop lab VMs so that they are only accumulating compute charges when being actively used.  "Bursting" load-balanced web applications - Provision a number of load-balanced VMs, but keep the minimum number of VMs running to support "normal" loads. Easily start-up the remaining VMs only when needed to support peak loads. Disaster Recovery - Start-up "cold" VMs when needed to recover from disaster scenarios. BUT ... there is a consideration to keep in mind when using the Windows Azure Management Portal to shutdown VMs: although performing a VM shutdown via the Windows Azure Management Portal causes that VM to no longer accumulate compute charges, it also deallocates the VM from fabric resources to which it was previously assigned.  These fabric resources include compute resources such as virtual CPU cores and memory, as well as network resources, such as IP addresses.  This means that when the VM is later started after being shutdown from the portal, the VM could be assigned a different IP address or placed on a different compute node within the fabric. In some cases, you may want to shutdown VMs using the old approach, where fabric resource assignments are maintained while the VM is in a shutdown state.  Specifically, you may wish to do this when temporarily shutting down or restarting a "7x24" VM as part of a maintenance activity.  Good news - you can still revert back to the old VM shutdown behavior when necessary by using the alternate VM shutdown approaches listed below.  Let's walk through each approach for performing a VM Shutdown action on Windows Azure so that we can understand the benefits and considerations of each... How many ways can I shutdown a VM? In Windows Azure Infrastructure Services, there's three general ways that can be used to safely shutdown VMs: Shutdown VM via Windows Azure Management Portal Shutdown Guest Operating System inside the VM Stop VM via Windows PowerShell using Windows Azure PowerShell Module Although each of these options performs a safe shutdown of the guest operation system and the VM itself, each option handles the VM shutdown end state differently. Shutdown VM via Windows Azure Management Portal When clicking the Shutdown button at the bottom of the Virtual Machines page in the Windows Azure Management Portal, the VM is safely shutdown and "deallocated" from fabric resources.  Shutdown button on Virtual Machines page in Windows Azure Management Portal  When the shutdown process completes, the VM will be shown on the Virtual Machines page with a "Stopped ( Deallocated )" status as shown in the figure below. Virtual Machine in a "Stopped (Deallocated)" Status "Deallocated" means that the VM configuration is no longer being actively associated with fabric resources, such as virtual CPUs, memory and networks. In this state, the VM will not continue to allocate compute charges, but since fabric resources are deallocated, the VM could receive a different internal IP address ( called "Dynamic IPs" or "DIPs" in Windows Azure ) the next time it is started.  TIP: If you are leveraging this shutdown option and consistency of DIPs is important to applications running inside your VMs, you should consider using virtual networks with your VMs.  Virtual networks permit you to assign a specific IP Address Space for use with VMs that are assigned to that virtual network.  As long as you start VMs in the same order in which they were originally provisioned, each VM should be reassigned the same DIP that it was previously using. What about consistency of External IP Addresses? Great question! External IP addresses ( called "Virtual IPs" or "VIPs" in Windows Azure ) are associated with the cloud service in which one or more Windows Azure VMs are running.  As long as at least 1 VM inside a cloud service remains in a "Running" state, the VIP assigned to a cloud service will be preserved.  If all VMs inside a cloud service are in a "Stopped ( Deallocated )" status, then the cloud service may receive a different VIP when VMs are next restarted. TIP: If consistency of VIPs is important for the cloud services in which you are running VMs, consider keeping one VM inside each cloud service in the alternate VM shutdown state listed below to preserve the VIP associated with the cloud service. Shutdown Guest Operating System inside the VM When performing a Guest OS shutdown or restart ( ie., a shutdown or restart operation initiated from the Guest OS running inside the VM ), the VM configuration will not be deallocated from fabric resources. In the figure below, the VM has been shutdown from within the Guest OS and is shown with a "Stopped" VM status rather than the "Stopped ( Deallocated )" VM status that was shown in the previous figure. Note that it may require a few minutes for the Windows Azure Management Portal to reflect that the VM is in a "Stopped" state in this scenario, because we are performing an OS shutdown inside the VM rather than through an Azure management endpoint. Virtual Machine in a "Stopped" Status VMs shown in a "Stopped" status will continue to accumulate compute charges, because fabric resources are still being reserved for these VMs.  However, this also means that DIPs and VIPs are preserved for VMs in this state, so you don't have to worry about VMs and cloud services getting different IP addresses when they are started in the future. Stop VM via Windows PowerShell In the latest version of the Windows Azure PowerShell Module, a new -StayProvisioned parameter has been added to the Stop-AzureVM cmdlet. This new parameter provides the flexibility to choose the VM configuration end result when stopping VMs using PowerShell: When running the Stop-AzureVM cmdlet without the -StayProvisioned parameter specified, the VM will be safely stopped and deallocated; that is, the VM will be left in a "Stopped ( Deallocated )" status just like the end result when a VM Shutdown operation is performed via the Windows Azure Management Portal.  When running the Stop-AzureVM cmdlet with the -StayProvisioned parameter specified, the VM will be safely stopped but fabric resource reservations will be preserved; that is the VM will be left in a "Stopped" status just like the end result when performing a Guest OS shutdown operation. So, with PowerShell, you can choose how Windows Azure should handle VM configuration and fabric resource reservations when stopping VMs on a case-by-case basis. TIP: It's important to note that the -StayProvisioned parameter is only available in the latest version of the Windows Azure PowerShell Module.  So, if you've previously downloaded this module, be sure to download and install the latest version to get this new functionality. Want to Learn More about Windows Azure Infrastructure Services? To learn more about Windows Azure Infrastructure Services, be sure to check-out these additional FREE resources: Become our next "Early Expert"! Complete the Early Experts "Cloud Quest" and build a multi-VM lab network in the cloud for FREE!  Build some cool scenarios! Check out our list of over 20+ Step-by-Step Lab Guides based on key scenarios that IT Pros are implementing on Windows Azure Infrastructure Services TODAY!  Looking forward to seeing you in the Cloud! - Keith Build Your Lab! Download Windows Server 2012 Don’t Have a Lab? Build Your Lab in the Cloud with Windows Azure Virtual Machines Want to Get Certified? Join our Windows Server 2012 "Early Experts" Study Group

  Read the article

• Networking in VirtualBox

  - by Fat Bloke

  Networking in VirtualBox is extremely powerful, but can also be a bit daunting, so here's a quick overview of the different ways you can setup networking in VirtualBox, with a few pointers as to which configurations should be used and when. VirtualBox allows you to configure up to 8 virtual NICs (Network Interface Controllers) for each guest vm (although only 4 are exposed in the GUI) and for each of these NICs you can configure: Which virtualized NIC-type is exposed to the Guest. Examples include: Intel PRO/1000 MT Server (82545EM),  AMD PCNet FAST III (Am79C973, the default) or  a Paravirtualized network adapter (virtio-net). How the NIC operates with respect to your Host's physical networking. The main modes are: Network Address Translation (NAT) Bridged networking Internal networking Host-only networking NAT with Port-forwarding The choice of NIC-type comes down to whether the guest has drivers for that NIC.  VirtualBox, suggests a NIC based on the guest OS-type that you specify during creation of the vm, and you rarely need to modify this. But the choice of networking mode depends on how you want to use your vm (client or server) and whether you want other machines on your network to see it. So let's look at each mode in a bit more detail... Network Address Translation (NAT) This is the default mode for new vm's and works great in most situations when the Guest is a "client" type of vm. (i.e. most network connections are outbound). Here's how it works: When the guest OS boots,  it typically uses DHCP to get an IP address. VirtualBox will field this DHCP request and tell the guest OS its assigned IP address and the gateway address for routing outbound connections. In this mode, every vm is assigned the same IP address (10.0.2.15) because each vm thinks they are on their own isolated network. And when they send their traffic via the gateway (10.0.2.2) VirtualBox rewrites the packets to make them appear as though they originated from the Host, rather than the Guest (running inside the Host). This means that the Guest will work even as the Host moves from network to network (e.g. laptop moving between locations), and from wireless to wired connections too. However, how does another computer initiate a connection into a Guest?  e.g. connecting to a web server running in the Guest. This is not (normally) possible using NAT mode as there is no route into the Guest OS. So for vm's running servers we need a different networking mode.... Bridged Networking Bridged Networking is used when you want your vm to be a full network citizen, i.e. to be an equal to your host machine on the network. In this mode, a virtual NIC is "bridged" to a physical NIC on your host, like this: The effect of this is that each VM has access to the physical network in the same way as your host. It can access any service on the network such as external DHCP services, name lookup services, and routing information just as the host does. Logically, the network looks like this: The downside of this mode is that if you run many vm's you can quickly run out of IP addresses or your network administrator gets fed up with you asking for statically assigned IP addresses. Secondly, if your host has multiple physical NICs (e.g. Wireless and Wired) you must reconfigure the bridge when your host jumps networks.  Hmm, so what if you want to run servers in vm's but don't want to involve your network administrator? Maybe one of the next 2 modes is for you... Internal Networking When you configure one or more vm's to sit on an Internal network, VirtualBox ensures that all traffic on that network stays within the host and is only visible to vm's on that virtual network. Configuration looks like this: The internal network ( in this example "intnet" ) is a totally isolated network and so is very "quiet". This is good for testing when you need a separate, clean network, and you can create sophisticated internal networks with vm's that provide their own services to the internal network. (e.g. Active Directory, DHCP, etc). Note that not even the Host is a member of the internal network, but this mode allows vm's to function even when the Host is not connected to a network (e.g. on a plane). Note that in this mode, VirtualBox provides no "convenience" services such as DHCP, so your machines must be statically configured or one of the vm's needs to provide a DHCP/Name service. Multiple internal networks are possible and you can configure vm's to have multiple NICs to sit across internal and other network modes and thereby provide routes if needed. But all this sounds tricky. What if you want an Internal Network that the host participates on with VirtualBox providing IP addresses to the Guests? Ah, then for this, you might want to consider Host-only Networking... Host-only Networking Host-only Networking is like Internal Networking in that you indicate which network the Guest sits on, in this case, "vboxnet0": All vm's sitting on this "vboxnet0" network will see each other, and additionally, the host can see these vm's too. However, other external machines cannot see Guests on this network, hence the name "Host-only". Logically, the network looks like this: This looks very similar to Internal Networking but the host is now on "vboxnet0" and can provide DHCP services. To configure how a Host-only network behaves, look in the VirtualBox Manager...Preferences...Network dialog: Port-Forwarding with NAT Networking Now you may think that we've provided enough modes here to handle every eventuality but here's just one more... What if you cart around a mobile-demo or dev environment on, say, a laptop and you have one or more vm's that you need other machines to connect into? And you are continually hopping onto different (customer?) networks. In this scenario: NAT - won't work because external machines need to connect in. Bridged - possibly an option, but does your customer want you eating IP addresses and can your software cope with changing networks? Internal - we need the vm(s) to be visible on the network, so this is no good. Host-only - same problem as above, we want external machines to connect in to the vm's. Enter Port-forwarding to save the day! Configure your vm's to use NAT networking; Add Port Forwarding rules; External machines connect to "host":"port number" and connections are forwarded by VirtualBox to the guest:port number specified. For example, if your vm runs a web server on port 80, you could set up rules like this:  ...which reads: "any connections on port 8080 on the Host will be forwarded onto this vm's port 80".  This provides a mobile demo system which won't need re-configuring every time you open your laptop lid. Summary VirtualBox has a very powerful set of options allowing you to set up almost any configuration your heart desires. For more information, check out the VirtualBox User Manual on Virtual Networking. -FB 

  Read the article

• When should I use Areas in TFS instead of Team Projects

  - by Martin Hinshelwood

  Well, it depends…. If you are a small company that creates a finite number of internal projects then you will find it easier to create a single project for each of your products and have TFS do the heavy lifting with reporting, SharePoint sites and Version Control. But what if you are not… Update 9th March 2010 Michael Fourie gave me some feedback which I have integrated. Ed Blankenship via @edblankenship offered encouragement and a nice quote. Ewald Hofman gave me a couple of Cons, and maybe a few more soon. Ewald’s company, Avanade, currently uses Areas, but it looks like the manual management is getting too much and the project is getting cluttered. What if you are likely to have hundreds of projects, possibly with a multitude of internal and external projects? You might have 1 project for a customer or 10. This is the situation that most consultancies find themselves in and thus they need a more sustainable and maintainable option. What I am advocating is that we should have 1 “Team Project” per customer, and use areas to create “sub projects” within that single “Team Project”. "What you describe is what we generally do internally and what we recommend. We make very heavy use of area path to categorize the work within a larger project." - Brian Harry, Microsoft Technical Fellow & Product Unit Manager for Team Foundation Server   "We tend to use areas to segregate multiple projects in the same team project and it works well." - Tiago Pascoal, Visual Studio ALM MVP   "In general, I believe this approach provides consistency [to multi-product engagements] and lowers the administration and maintenance costs. All good." - Michael Fourie, Visual Studio ALM MVP   “@MrHinsh BTW, I'm very much a fan of very large, if not huge, team projects in TFS. Just FYI :) Use Areas & Iterations.” Ed Blankenship, Visual Studio ALM MVP   This would mean that SSW would have a single Team Project called “SSW” that contains all of our internal projects and consequently all of the Areas and Iteration move down one hierarchy to accommodate this. Where we would have had “\SSW\Sprint 1” we now have “\SSW\SqlDeploy\Sprint1” with “SqlDeploy” being our internal project. At the moment SSW has over 70 internal projects and more than 170 total projects in TFS. This method has long term benefits that help to simplify the support model for companies that often have limited internal support time and many projects. But, there are implications as TFS does not provide this model “out-of-the-box”. These implications stretch across Areas, Iterations, Queries, Project Portal and Version Control. Michael made a good comment, he said: I agree with your approach, assuming that in a multi-product engagement with a client, they are happy to adopt the same process template across all products. If they are not, then it’ll either be easy to convince them or there is a valid reason for having a different template - Michael Fourie, Visual Studio ALM MVP   At SSW we have a standard template that we use and this is applied across the board, to all of our projects. We even apply any changes to the core process template to all of our existing projects as well. If you have multiple projects for the same clients on multiple templates and you want to keep it that way, then this approach will not work for you. However, if you want to standardise as we have at SSW then this approach may benefit you as well. Implications around Areas Areas should be used for topological classification/isolation of work items. You can think of this as architecture areas, organisational areas or even the main features of your application. In our scenario there is an additional top level item that represents the Project / Product that we want to chop our Team Project into. Figure: Creating a sub area to represent a product/project is easy. <teamproject> <teamproject>\<Functional Area/module whatever> Becomes: <teamproject> <teamproject>\<ProjectName>\ <teamproject>\<ProjectName>\<Functional Area/module whatever> Implications around Iterations Iterations should be used for chronological classification/isolation of work items. This could include isolated time boxes, milestones or release timelines and really depends on the logical flow of your project or projects. Due to the new level in Area we need to add the same level to Iteration. This is primarily because it is unlikely that the sprints in each of your projects/products will start and end at the same time. This is just a reality of managing multiple projects. Figure: Adding the same Area value to Iteration as the top level item adds flexibility to Iteration. <teamproject>\Sprint 1 Or <teamproject>\Release 1\Sprint 1 Becomes: <teamproject>\<ProjectName>\Sprint 1 Or <teamproject>\<ProjectName>\Release 1\Sprint 1 Implications around Queries Queries are used to filter your work items based on a specified level of granularity. There are a number of queries that are built into a project created using the MSF Agile 5.0 template, but we now have multiple projects and it would be a pain to have to edit all of the work items every time we changed project, and that would only allow one team to work on one project at a time.   Figure: The Queries that are created in a normal MSF Agile 5.0 project do not quite suit our new needs. In order for project contributors to be able to query based on their project we need a couple of things. The first thing I did was to create an “_Area Template” folder that has a copy of the project layout with all the queries setup to filter based on the “_Area Template” Area and the “_Sprint template” you can see in the Area and Iteration views. Figure: The template is currently easily drag and drop, but you then need to edit the queries to point at the right Area and Iteration. This needs a tool. I then created an “Areas” folder to hold all of the area specific queries. So, when you go to create a new TFS Sub-Project you just drag “_Area Template” while holding “Ctrl” and drop it onto “Areas”. There is a little setup here. That said I managed it in around 10 minutes which is not so bad, and I can imagine it being quite easy to build a tool to create these queries Figure: These new queries can be configured in around 10 minutes, which includes setting up the Area and Iteration as well. Version Control What about your source code? Well, that is the easiest of the lot. Just create a sub folder for each of your projects/products.   Figure: Creating sub folders in source control is easy as “Right click | Create new folder”. <teamproject>\DEV\Main\ Becomes: <teamproject>\<ProjectName>\DEV\Main\ Conclusion I think it is up to each company to make a call on how you want to configure your Team Projects and it depends completely on how many projects/products you are going to have for each customer including yourself. If we decide to utilise this route it will require some configuration to get our 170+ projects into this format, and I will probably be writing some tools to help. Pros You only have one project to upgrade when a process template changes – After going through an upgrade of over 170 project prior to the changes in the RC I can tell you that that many projects is no fun. Standardises your Process Template – You will always have the same Process implementation across projects/products without exception You get tighter control over the permissions – Yes, you can do this on a standard Team Project, but it gets a lot easier with practice. You can “move” work items from one “product” to another – Have we not always wanted to do that. You can rename your projects – Wahoo: everyone wants to do this, now you can. One set of Reporting Services reports to manage – You set an area and iteration to run reports anyway, so you may as well set both. Simplified Check-In Policies– There is only one set of check-in policies per client. This simplifies administration of policies. Simplified Alerts – As alerts are applied across multiple projects this simplifies your alert rules as per client. Cons All of these cons could be mitigated by a custom tool that helps automate creation of “Sub-projects” within Team Projects. This custom tool could create areas, Iteration, permissions, SharePoint and queries. It just does not exist yet :) You need to configure the Areas and Iterations You need to configure the permissions You may need to configure sub sites for SharePoint (depends on your requirement) – If you have two projects/products in the same Team Project then you will not see the burn down for each one out-of-the-box, but rather a cumulative for the Team Project. This is not really that much of a problem as you would have to configure your burndown graphs for your current iteration anyway. note: When you create a sub site to a TFS linked portal it will inherit the settings of its parent site :) This is fantastic as it means that you can easily create sub sites and then set the Area and Iteration path in each of the reports to be the correct one. Every team wants their own customization (via Ewald Hofman) - small teams of 2 persons against teams of 30 – or even outsourcing – need their own process, you cannot allow that because everybody gets the same work item types. note: Luckily at SSW this is not a problem as our template is standardised across all projects and customers. Large list of builds (via Ewald Hofman) – As the build list in Team Explorer is just a flat list it can get very cluttered. note: I would mitigate this by removing any build that has not been run in over 30 days. The build template and workflow will still be available in version control, but it will clean the list. Feedback Now that I have explained this method, what do you think? What other pros and cons can you see? What do you think of this approach? Will you be using it? What tools would you like to support you?   Technorati Tags: Visual Studio ALM,TFS Administration,TFS,Team Foundation Server,Project Planning,TFS Customisation

  Read the article

• Transactional Messaging in the Windows Azure Service Bus

  - by Alan Smith

  Introduction I’m currently working on broadening the content in the Windows Azure Service Bus Developer Guide. One of the features I have been looking at over the past week is the support for transactional messaging. When using the direct programming model and the WCF interface some, but not all, messaging operations can participate in transactions. This allows developers to improve the reliability of messaging systems. There are some limitations in the transactional model, transactions can only include one top level messaging entity (such as a queue or topic, subscriptions are no top level entities), and transactions cannot include other systems, such as databases. As the transaction model is currently not well documented I have had to figure out how things work through experimentation, with some help from the development team to confirm any questions I had. Hopefully I’ve got the content mostly correct, I will update the content in the e-book if I find any errors or improvements that can be made (any feedback would be very welcome). I’ve not had a chance to look into the code for transactions and asynchronous operations, maybe that would make a nice challenge lab for my Windows Azure Service Bus course. Transactional Messaging Messaging entities in the Windows Azure Service Bus provide support for participation in transactions. This allows developers to perform several messaging operations within a transactional scope, and ensure that all the actions are committed or, if there is a failure, none of the actions are committed. There are a number of scenarios where the use of transactions can increase the reliability of messaging systems. Using TransactionScope In .NET the TransactionScope class can be used to perform a series of actions in a transaction. The using declaration is typically used de define the scope of the transaction. Any transactional operations that are contained within the scope can be committed by calling the Complete method. If the Complete method is not called, any transactional methods in the scope will not commit.   // Create a transactional scope. using (TransactionScope scope = new TransactionScope()) {     // Do something.       // Do something else.       // Commit the transaction.     scope.Complete(); }     In order for methods to participate in the transaction, they must provide support for transactional operations. Database and message queue operations typically provide support for transactions. Transactions in Brokered Messaging Transaction support in Service Bus Brokered Messaging allows message operations to be performed within a transactional scope; however there are some limitations around what operations can be performed within the transaction. In the current release, only one top level messaging entity, such as a queue or topic can participate in a transaction, and the transaction cannot include any other transaction resource managers, making transactions spanning a messaging entity and a database not possible. When sending messages, the send operations can participate in a transaction allowing multiple messages to be sent within a transactional scope. This allows for “all or nothing” delivery of a series of messages to a single queue or topic. When receiving messages, messages that are received in the peek-lock receive mode can be completed, deadlettered or deferred within a transactional scope. In the current release the Abandon method will not participate in a transaction. The same restrictions of only one top level messaging entity applies here, so the Complete method can be called transitionally on messages received from the same queue, or messages received from one or more subscriptions in the same topic. Sending Multiple Messages in a Transaction A transactional scope can be used to send multiple messages to a queue or topic. This will ensure that all the messages will be enqueued or, if the transaction fails to commit, no messages will be enqueued.     An example of the code used to send 10 messages to a queue as a single transaction from a console application is shown below.   QueueClient queueClient = messagingFactory.CreateQueueClient(Queue1);   Console.Write("Sending");   // Create a transaction scope. using (TransactionScope scope = new TransactionScope()) {     for (int i = 0; i < 10; i++)     {         // Send a message         BrokeredMessage msg = new BrokeredMessage("Message: " + i);         queueClient.Send(msg);         Console.Write(".");     }     Console.WriteLine("Done!");     Console.WriteLine();       // Should we commit the transaction?     Console.WriteLine("Commit send 10 messages? (yes or no)");     string reply = Console.ReadLine();     if (reply.ToLower().Equals("yes"))     {         // Commit the transaction.         scope.Complete();     } } Console.WriteLine(); messagingFactory.Close();     The transaction scope is used to wrap the sending of 10 messages. Once the messages have been sent the user has the option to either commit the transaction or abandon the transaction. If the user enters “yes”, the Complete method is called on the scope, which will commit the transaction and result in the messages being enqueued. If the user enters anything other than “yes”, the transaction will not commit, and the messages will not be enqueued. Receiving Multiple Messages in a Transaction The receiving of multiple messages is another scenario where the use of transactions can improve reliability. When receiving a group of messages that are related together, maybe in the same message session, it is possible to receive the messages in the peek-lock receive mode, and then complete, defer, or deadletter the messages in one transaction. (In the current version of Service Bus, abandon is not transactional.)   The following code shows how this can be achieved. using (TransactionScope scope = new TransactionScope()) {       while (true)     {         // Receive a message.         BrokeredMessage msg = q1Client.Receive(TimeSpan.FromSeconds(1));         if (msg != null)         {             // Wrote message body and complete message.             string text = msg.GetBody<string>();             Console.WriteLine("Received: " + text);             msg.Complete();         }         else         {             break;         }     }     Console.WriteLine();       // Should we commit?     Console.WriteLine("Commit receive? (yes or no)");     string reply = Console.ReadLine();     if (reply.ToLower().Equals("yes"))     {         // Commit the transaction.         scope.Complete();     }     Console.WriteLine(); }     Note that if there are a large number of messages to be received, there will be a chance that the transaction may time out before it can be committed. It is possible to specify a longer timeout when the transaction is created, but It may be better to receive and commit smaller amounts of messages within the transaction. It is also possible to complete, defer, or deadletter messages received from more than one subscription, as long as all the subscriptions are contained in the same topic. As subscriptions are not top level messaging entities this scenarios will work. The following code shows how this can be achieved. try {     using (TransactionScope scope = new TransactionScope())     {         // Receive one message from each subscription.         BrokeredMessage msg1 = subscriptionClient1.Receive();         BrokeredMessage msg2 = subscriptionClient2.Receive();           // Complete the message receives.         msg1.Complete();         msg2.Complete();           Console.WriteLine("Msg1: " + msg1.GetBody<string>());         Console.WriteLine("Msg2: " + msg2.GetBody<string>());           // Commit the transaction.         scope.Complete();     } } catch (Exception ex) {     Console.WriteLine(ex.Message); }     Unsupported Scenarios The restriction of only one top level messaging entity being able to participate in a transaction makes some useful scenarios unsupported. As the Windows Azure Service Bus is under continuous development and new releases are expected to be frequent it is possible that this restriction may not be present in future releases. The first is the scenario where messages are to be routed to two different systems. The following code attempts to do this.   try {     // Create a transaction scope.     using (TransactionScope scope = new TransactionScope())     {         BrokeredMessage msg1 = new BrokeredMessage("Message1");         BrokeredMessage msg2 = new BrokeredMessage("Message2");           // Send a message to Queue1         Console.WriteLine("Sending Message1");         queue1Client.Send(msg1);           // Send a message to Queue2         Console.WriteLine("Sending Message2");         queue2Client.Send(msg2);           // Commit the transaction.         Console.WriteLine("Committing transaction...");         scope.Complete();     } } catch (Exception ex) {     Console.WriteLine(ex.Message); }     The results of running the code are shown below. When attempting to send a message to the second queue the following exception is thrown: No active Transaction was found for ID '35ad2495-ee8a-4956-bbad-eb4fedf4a96e:1'. The Transaction may have timed out or attempted to span multiple top-level entities such as Queue or Topic. The server Transaction timeout is: 00:01:00..TrackingId:947b8c4b-7754-4044-b91b-4a959c3f9192_3_3,TimeStamp:3/29/2012 7:47:32 AM.   Another scenario where transactional support could be useful is when forwarding messages from one queue to another queue. This would also involve more than one top level messaging entity, and is therefore not supported.   Another scenario that developers may wish to implement is performing transactions across messaging entities and other transactional systems, such as an on-premise database. In the current release this is not supported.   Workarounds for Unsupported Scenarios There are some techniques that developers can use to work around the one top level entity limitation of transactions. When sending two messages to two systems, topics and subscriptions can be used. If the same message is to be sent to two destinations then the subscriptions would have the default subscriptions, and the client would only send one message. If two different messages are to be sent, then filters on the subscriptions can route the messages to the appropriate destination. The client can then send the two messages to the topic in the same transaction.   In scenarios where a message needs to be received and then forwarded to another system within the same transaction topics and subscriptions can also be used. A message can be received from a subscription, and then sent to a topic within the same transaction. As a topic is a top level messaging entity, and a subscription is not, this scenario will work.

  Read the article

• Joins in LINQ to SQL

  - by rajbk

  The following post shows how to write different types of joins in LINQ to SQL. I am using the Northwind database and LINQ to SQL for these examples. NorthwindDataContext dataContext = new NorthwindDataContext(); Inner Join var q1 = from c in dataContext.Customers join o in dataContext.Orders on c.CustomerID equals o.CustomerID select new { c.CustomerID, c.ContactName, o.OrderID, o.OrderDate }; SELECT [t0].[CustomerID], [t0].[ContactName], [t1].[OrderID], [t1].[OrderDate]FROM [dbo].[Customers] AS [t0]INNER JOIN [dbo].[Orders] AS [t1] ON [t0].[CustomerID] = [t1].[CustomerID] Left Join var q2 = from c in dataContext.Customers join o in dataContext.Orders on c.CustomerID equals o.CustomerID into g from a in g.DefaultIfEmpty() select new { c.CustomerID, c.ContactName, a.OrderID, a.OrderDate }; SELECT [t0].[CustomerID], [t0].[ContactName], [t1].[OrderID] AS [OrderID], [t1].[OrderDate] AS [OrderDate]FROM [dbo].[Customers] AS [t0]LEFT OUTER JOIN [dbo].[Orders] AS [t1] ON [t0].[CustomerID] = [t1].[CustomerID] Inner Join on multiple //We mark our anonymous type properties as a and b otherwise//we get the compiler error "Type inferencce failed in the call to 'Join’var q3 = from c in dataContext.Customers join o in dataContext.Orders on new { a = c.CustomerID, b = c.Country } equals new { a = o.CustomerID, b = "USA" } select new { c.CustomerID, c.ContactName, o.OrderID, o.OrderDate }; SELECT [t0].[CustomerID], [t0].[ContactName], [t1].[OrderID], [t1].[OrderDate]FROM [dbo].[Customers] AS [t0]INNER JOIN [dbo].[Orders] AS [t1] ON ([t0].[CustomerID] = [t1].[CustomerID]) AND ([t0].[Country] = @p0) Inner Join on multiple with ‘OR’ clause var q4 = from c in dataContext.Customers from o in dataContext.Orders.Where(a => a.CustomerID == c.CustomerID || c.Country == "USA") select new { c.CustomerID, c.ContactName, o.OrderID, o.OrderDate }; SELECT [t0].[CustomerID], [t0].[ContactName], [t1].[OrderID], [t1].[OrderDate]FROM [dbo].[Customers] AS [t0], [dbo].[Orders] AS [t1]WHERE ([t1].[CustomerID] = [t0].[CustomerID]) OR ([t0].[Country] = @p0) Left Join on multiple with ‘OR’ clause var q5 = from c in dataContext.Customers from o in dataContext.Orders.Where(a => a.CustomerID == c.CustomerID || c.Country == "USA").DefaultIfEmpty() select new { c.CustomerID, c.ContactName, o.OrderID, o.OrderDate }; SELECT [t0].[CustomerID], [t0].[ContactName], [t1].[OrderID] AS [OrderID], [t1].[OrderDate] AS [OrderDate]FROM [dbo].[Customers] AS [t0]LEFT OUTER JOIN [dbo].[Orders] AS [t1] ON ([t1].[CustomerID] = [t0].[CustomerID]) OR ([t0].[Country] = @p0)

  Read the article

• Open vSwitch and Xen Private Networks

  - by Joe

  I've read about the possibilities of using Open vSwitch with Xen to route traffic between domUs on multiple physical hosts. I'd like to be able to group the multiple domUs I have spread out across multiple physical hosts into a number of private networks. However, I've found no documentation on how to integrate Open vSwitch with Xen (rather than XenServer) and am unsure how I should go about doing so and then creating the private networks described. As you might have gathered then - from research I think Open vSwitch can do what I need it to, but I just can't find anything giving me a push in the right direction of how to actually use it to do so! This may well be because Open vSwitch is quite new (version 1.0 released on May 17). Any pointers in the right direction would be much appreciated!

  Read the article

• Regular Expressions Cookbook Is in The Money—Win a Copy

  - by Jan Goyvaerts

  %COOKBOOKFRAME%You may have heard some people say that most book authors never get any royalties. That’s not true because most authors get an advance royalty that is paid before the book is published. That’s the author’s main incentive for writing the book, at least as far as money is concerned. (If money is your main concern, don’t write books.) What is true is that most authors never see any money beyond the advance royalty. Royalty rates are very low. A 10% royalty of the publisher’s price is considered normal. The publisher’s price is usually 45% of the retail price. So if you pay full price in a bookstore, the author gets 4.5% of your money. If there’s more than one author, they split the royalty. It doesn’t take a math degree to figure out that a book needs to sell quite a few copies for the royalty to add up to a meaningful amount of money. But Steven and I must have done something right. Regular Expressions Cookbook is in the money. My royalty statement for the 3rd quartier of 2009, which is the 2nd quarter that the book was on the market, came with a check. I actually received it last month but didn’t get around to blogging about. The amount of the check is insignificant. The point is that the balance is no longer negative. I’m taking this opportunity to pat myself and my co-author on the back. To celebrate the occassion O’Reilly has offered to sponsor a give-away of five (5) copies of Regular Expressions Cookbook. These are the rules of the game: You must post a comment to this blog article including your actual name and actual email address. Names are published, email addresses are not. Comments are moderated by myself (Jan Goyvaerts). If I consider a comment to be offensive or spam it will not be published and not be eligible for any prize. If you don’t know what to say in the comment, just wish me a happy 100000nd birthday, so I don’t have to feel so bad about entering the 6-bit era. Each person commenting has only one chance to win, regardless of the number of comments posted. O’Reilly will be provided with the names and email addresses of the winners (and those email addresses only) in order to arrange delivery. Each winner can choose to receive a printed copy or ebook (DRM-free PDF). If you choose the printed book, O’Reilly pays for shipping to anywhere in the world but not for any duties or taxes your country may impose on books imported from the USA. If you choose the ebook, you’ll need to create an O’Reilly account that is then granted access to the PDF download. You can make your choice after you’ve won, so it doesn’t influence your chance of winning. Contest ends 28 February 2010, GMT+7 (Thai time). Chosen by five calls to Random(78)+1 in Delphi 2010, the winners are: 48: Xiaozu 45: David Chisholm 19: Miquel Burns 33: Aaron Rice 17: David Laing Thanks to everybody who participated. The winners have been notified by email on how to collect their prize.

  Read the article

• links for 2010-04-15

  - by Bob Rhubart

  e-Energy 2010 in Passau : Franz Haberhauer's Weblog Fresh off his participation in a panel at the 1st Int' Conf. on Energy-Efficient Computing and Networking at the University of Passau, Germany, Franz Haberhauer offers some background on the CoolThreads/Chip Mulitthreading Technology and its role in greener datacenters. (tags: oracle sun datacenter Mulitthreading) Oracle Enterprise Manager Grid Control: New Recommended Bundle Patch (APR 2010) - 9405592 for Patch Automation on EM 10.2.0.5 Notes and a short FAQ on the Recommended Bundle Patch 9405592 for Oracle Enterprise Manager Grid Control. (tags: architect entarch grid oracle otn) Vijaykumar Yenne: Customizing Spaces UI Vijaykumar Yyenne explains how to leverage the Extend Spaces Project on the Oracle Technology Network to customize Oracle WebCenter site templates. (tags: enterprise2.0 oracle otn webcenter) Knut Vatsendvik: Catch Me If You Can "Suppose you have a Proxy based Web Service using Oracle Service Bus. In a stage in the request pipeline, you are using a Publish action to publish the incoming message to a JMS queue using a Business Service. What if the outbound transport provider throws an exception (outside of your pipeline)? Is your pipeline able to catch the error with an error handler?" -- Knut Vatsendvik (tags: oracle otn soa esb weblogic architect) Pete Wang: Coherence Configuration For Multiple HA SOA Domains Quick tips from Pete Wang on the Oracle Coherence settings necessary for creating multiple SOA HA domains. (tags: architect coherence oracle otn soa) Warren Baird: New Walkthrough Capability in AutoVue 20 Warren Baird describes new features in Oracle AutoVue 20 that allow viewing a 3D model of a building from the inside. (tags: architect entarch oracle otn) Peter Wang: How to implement multi-source XSLT mapping in Oracle SOA Suite 11g BPEL In SOA 11g, you can create a XSLT mapper that uses multiple sources as the input. Pete Wang shows you how. (tags: oracle otn soa bpel architect)

  Read the article

• Silverlight Cream for May 30, 2010 -- #873

  - by Dave Campbell

  In this Issue: Matthias Shapiro, Colin Blair(-2-), Mike Snow, Marlon Grech, Victor Gaudioso. Shoutout: If you're going to be anywhere near Mission Viejo, California on June 19th, set your calendar for this Victor Gaudioso event: New Speaking Event: Microsoft Book Signing/Silverlight 4 Presentation SilverLaw has another example of his Flexible surface app up: Drag & Drop Flexible Surface - Silverlight 4 From SilverlightCream.com: Silverlight 4 Binding and StringFormat in XAML Matthias Shapiro has a discussion posted about StringFormat binding in Silverlight 4 ... he dug in hard on this... well worth a read. View Model Collection Properties for WCF RIA Services Colin Blair is discussing some possibilities for exposing collections of entities from the ViewModel... his favorite: PagedCollectionView. The next post discusses this deeper. Advanced Paged Collection View Colin Blair continues in more depth on the PagedCollectionView, this time handling paging, sorting, and multiple loads. Silverlight Tip of the day #25 – Detecting Validation Errors on Submit Mike Snow's latest Tip of the Day is up and is about validation - specifically validating after your user has pressed "OK" INotifyPropertyChanged… I am fed up of handling events just to know when a property changed Marlon Grech has an Rx-less solution to code notifications of properties changing... this is a WPF and Silverlight solution and all the code is downloadable. New Silverlight Video Tutorial: How to Add Multiple BitmapEffects to One Object Victor Gaudioso's latest outing is in response to a query from a reader and is a video tutorial showing how to add multiple bitmap effects to one object. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

  Read the article

• Site too large to officially use Google Analytics?

  - by Jeff Atwood

  We just got this email from the Google Analytics team: We love that you love our product and use it as much as you do. We have observed however, that a website you are tracking with Google Analytics is sending over 1 million hits per day to Google Analytics servers. This is well above the "5 million pageviews per month per account" limit specified in the Google Analytics Terms of Service. Processing this amount of data multiple times a day takes up valuable resources that enable us to continue to develop the product for all Google Analytics users. Processing this amount of data multiple times a day takes up valuable resources that enable us to continue to develop the product for all Google Analytics users. As such, starting August 23rd, 2010, the metrics in your reports will be updated once a day, as opposed to multiple times during the course of the day. You will continue to receive all the reports and features in Google Analytics as usual. The only change will be that data for a given day will appear the following day. We trust you understand the reasons for this change. I totally respect this decision, and I think it's very generous to not kick us out. But how do we do this the right way -- what's the official, blessed Google way to use Google Analytics if you're a "whale" website with lots of hits per day? Or, are there other analytics services that would be more appropriate for very large websites?

  Read the article

• New Bundling and Minification Support (ASP.NET 4.5 Series)

  - by ScottGu

  This is the sixth in a series of blog posts I'm doing on ASP.NET 4.5. The next release of .NET and Visual Studio include a ton of great new features and capabilities.  With ASP.NET 4.5 you'll see a bunch of really nice improvements with both Web Forms and MVC - as well as in the core ASP.NET base foundation that both are built upon. Today’s post covers some of the work we are doing to add built-in support for bundling and minification into ASP.NET - which makes it easy to improve the performance of applications.  This feature can be used by all ASP.NET applications, including both ASP.NET MVC and ASP.NET Web Forms solutions. Basics of Bundling and Minification As more and more people use mobile devices to surf the web, it is becoming increasingly important that the websites and apps we build perform well with them. We’ve all tried loading sites on our smartphones – only to eventually give up in frustration as it loads slowly over a slow cellular network.  If your site/app loads slowly like that, you are likely losing potential customers because of bad performance.  Even with powerful desktop machines, the load time of your site and perceived performance can make an enormous customer perception. Most websites today are made up of multiple JavaScript and CSS files to separate the concerns and keep the code base tight. While this is a good practice from a coding point of view, it often has some unfortunate consequences for the overall performance of the website.  Multiple JavaScript and CSS files require multiple HTTP requests from a browser – which in turn can slow down the performance load time.  Simple Example Below I’ve opened a local website in IE9 and recorded the network traffic using IE’s built-in F12 developer tools. As shown below, the website consists of 5 CSS and 4 JavaScript files which the browser has to download. Each file is currently requested separately by the browser and returned by the server, and the process can take a significant amount of time proportional to the number of files in question. Bundling ASP.NET is adding a feature that makes it easy to “bundle” or “combine” multiple CSS and JavaScript files into fewer HTTP requests. This causes the browser to request a lot fewer files and in turn reduces the time it takes to fetch them.   Below is an updated version of the above sample that takes advantage of this new bundling functionality (making only one request for the JavaScript and one request for the CSS): The browser now has to send fewer requests to the server. The content of the individual files have been bundled/combined into the same response, but the content of the files remains the same - so the overall file size is exactly the same as before the bundling.   But notice how even on a local dev machine (where the network latency between the browser and server is minimal), the act of bundling the CSS and JavaScript files together still manages to reduce the overall page load time by almost 20%.  Over a slow network the performance improvement would be even better. Minification The next release of ASP.NET is also adding a new feature that makes it easy to reduce or “minify” the download size of the content as well.  This is a process that removes whitespace, comments and other unneeded characters from both CSS and JavaScript. The result is smaller files, which will download and load in a browser faster.  The graph below shows the performance gain we are seeing when both bundling and minification are used together: Even on my local dev box (where the network latency is minimal), we now have a 40% performance improvement from where we originally started.  On slow networks (and especially with international customers), the gains would be even more significant. Using Bundling and Minification inside ASP.NET The upcoming release of ASP.NET makes it really easy to take advantage of bundling and minification within projects and see performance gains like in the scenario above. The way it does this allows you to avoid having to run custom tools as part of your build process –  instead ASP.NET has added runtime support to perform the bundling/minification for you dynamically (caching the results to make sure perf is great).  This enables a really clean development experience and makes it super easy to start to take advantage of these new features. Let’s assume that we have a simple project that has 4 JavaScript files and 6 CSS files: Bundling and Minifying the .css files Let’s say you wanted to reference all of the stylesheets in the “Styles” folder above on a page.  Today you’d have to add multiple CSS references to get all of them – which would translate into 6 separate HTTP requests: The new bundling/minification feature now allows you to instead bundle and minify all of the .css files in the Styles folder – simply by sending a URL request to the folder (in this case “styles”) with an appended “/css” path after it.  For example:    This will cause ASP.NET to scan the directory, bundle and minify the .css files within it, and send back a single HTTP response with all of the CSS content to the browser.  You don’t need to run any tools or pre-processor to get this behavior.  This enables you to cleanly separate your CSS into separate logical .css files and maintain a very clean development experience – while not taking a performance hit at runtime for doing so.  The Visual Studio designer will also honor the new bundling/minification logic as well – so you’ll still get a WYSWIYG designer experience inside VS as well. Bundling and Minifying the JavaScript files Like the CSS approach above, if we wanted to bundle and minify all of our JavaScript into a single response we could send a URL request to the folder (in this case “scripts”) with an appended “/js” path after it:   This will cause ASP.NET to scan the directory, bundle and minify the .js files within it, and send back a single HTTP response with all of the JavaScript content to the browser.  Again – no custom tools or builds steps were required in order to get this behavior.  And it works with all browsers. Ordering of Files within a Bundle By default, when files are bundled by ASP.NET they are sorted alphabetically first, just like they are shown in Solution Explorer. Then they are automatically shifted around so that known libraries and their custom extensions such as jQuery, MooTools and Dojo are loaded before anything else. So the default order for the merged bundling of the Scripts folder as shown above will be: Jquery-1.6.2.js Jquery-ui.js Jquery.tools.js a.js By default, CSS files are also sorted alphabetically and then shifted around so that reset.css and normalize.css (if they are there) will go before any other file. So the default sorting of the bundling of the Styles folder as shown above will be: reset.css content.css forms.css globals.css menu.css styles.css The sorting is fully customizable, though, and can easily be changed to accommodate most use cases and any common naming pattern you prefer.  The goal with the out of the box experience, though, is to have smart defaults that you can just use and be successful with. Any number of directories/sub-directories supported In the example above we just had a single “Scripts” and “Styles” folder for our application.  This works for some application types (e.g. single page applications).  Often, though, you’ll want to have multiple CSS/JS bundles within your application – for example: a “common” bundle that has core JS and CSS files that all pages use, and then page specific or section specific files that are not used globally. You can use the bundling/minification support across any number of directories or sub-directories in your project – this makes it easy to structure your code so as to maximize the bunding/minification benefits.  Each directory by default can be accessed as a separate URL addressable bundle.  Bundling/Minification Extensibility ASP.NET’s bundling and minification support is built with extensibility in mind and every part of the process can be extended or replaced. Custom Rules In addition to enabling the out of the box - directory-based - bundling approach, ASP.NET also supports the ability to register custom bundles using a new programmatic API we are exposing.  The below code demonstrates how you can register a “customscript” bundle using code within an application’s Global.asax class.  The API allows you to add/remove/filter files that go into the bundle on a very granular level:     The above custom bundle can then be referenced anywhere within the application using the below <script> reference:     Custom Processing You can also override the default CSS and JavaScript bundles to support your own custom processing of the bundled files (for example: custom minification rules, support for Saas, LESS or Coffeescript syntax, etc). In the example below we are indicating that we want to replace the built-in minification transforms with a custom MyJsTransform and MyCssTransform class. They both subclass the CSS and JavaScript minifier respectively and can add extra functionality:     The end result of this extensibility is that you can plug-into the bundling/minification logic at a deep level and do some pretty cool things with it. 2 Minute Video of Bundling and Minification in Action Mads Kristensen has a great 90 second video that shows off using the new Bundling and Minification feature.  You can watch the 90 second video here. Summary The new bundling and minification support within the next release of ASP.NET will make it easier to build fast web applications.  It is really easy to use, and doesn’t require major changes to your existing dev workflow.  It is also supports a rich extensibility API that enables you to customize it however you want. You can easily take advantage of this new support within ASP.NET MVC, ASP.NET Web Forms and ASP.NET Web Pages based applications. Hope this helps, Scott P.S. In addition to blogging, I use Twitter to-do quick posts and share links. My Twitter handle is: @scottgu

  Read the article

• Questions, Knowledge Checks and Assessments

  - by ted.henson

  Questions should be used to reinforce concepts throughout the title. You have the option to include questions in the course, in assessments, in Knowledge Checks, or in any combination. Questions are required for creating knowledge checks and assessments. It is important to remember that questions that are not in assessments are not tracked. Be sure to structure your outline so that questions are added to the appropriate assignable unit. I usually recommend that questions appear directly below their relative section. This serves two purposes. First, it helps ensure that the related content and question stay relative to one another. Secondly, it ensures that when the "link to subject" option is used it will relate back to the relative content. Knowledge checks are created using the questions that have been added to the related assignable unit. Use Knowledge Checks to give users an additional opportunity to review what they have learned. Knowledge Check allows users to check their own knowledge without being tracked or scored. Many users like having this self check option, especially if they know they are going to be tested later. Each assignable unit can have its own Knowledge Check. Assessments provide a way to measure knowledge or understanding of the course material. The results of each assessment are scored and tracked. Assessments are created using the questions that have been added to the relative assignable unit(s). Each assignable unit, including the Title AU, can have multiple assessments. Consider how your knowledge paths will be structured when planning your assessments. For instance, you can create a multiple-activity knowledge path, with multiple assessments from the same title or assignable unit. Also remember, in Manager an assessment can be either a pre or post assessment. Pre-assessments allow the student to discover what is already known in a specific topic or subject and important if the personal course feature is being used. Post-assessments allow you test the student knowledge or understanding after completing the material.

  Read the article

• Delay between printing via lp in opensuse

  - by adamweeks

  I am experiencing a 10-15 second delay when printing multiple documents to a barcode printer in opensuse. I have had the same setup on other systems with older versions of opensuse without any issue. The setup is as follows: The print queue is setup as a "generic with driver Raw Queue". The files being sent down to the printers are simple text files with the lp command: lp -dprinter1 /path/file The printer is a JetDirect compatible device (Intermec brand) with a standard 9100 port socket setup. If I send a multi-page document to the printer, it will print nonstop the multiple pages. If I send 2 or more text files down via separate "lp" commands, the delay will be there between each printout. I've tried multiple different printers and they all experience the same issue.

  Read the article

• Dryad and DryadLINQ from MSR

  - by Daniel Moth

  Microsoft Research (MSR) researches technologies, incubates projects which many times result in technology that looks like a ready-to-use product (but it is important to understand that these are not the same as products built by the various… actual product teams here at Microsoft). A very popular MSR project has been DryadLINQ, which itself builds on Dryad. To learn more follow the project pages I just linked to and I also recommend this 1-hour channel 9 video. If you only have 3 minutes, watch this great elevator pitch instead. You can also stay tuned on the official blog, which includes a post that refers to internal adoption e.g by Bing, a quick DryadLINQ code example, and some history on how DryadLINQ generalizes the MapReduce pattern and makes it accessible to regular programmers (see this post and that post). Essentially, the DryadLINQ framework (building on the Dryad runtime) allows developers to re-use their LINQ skills for creating/generating programs that process large multi-gigabyte/terabyte datasets across 100s-1000s of machines. One way to think about it is that just as Parallel LINQ allows LINQ developers to seamlessly use multiple cores from a single process on a single machine, DryadLINQ allows LINQ developers to seamlessly use multiple machines for their data parallel algorithms. In the former scenario the motivation was speed of execution, in the latter it is speed of execution AND processing large datasets that simply don't fit on a single machine. Whenever I hear about execution of parallel code on multiple machines on the Microsoft platform, I immediately think of Windows HPC Server. Indeed Dryad and DryadLINQ were made available for Windows HPC Server and I encourage you to watch the PDC session on this topic: Data-Intensive Computing on Windows HPC Server with the DryadLINQ Framework. Watch this space… Comments about this post welcome at the original blog.

  Read the article

• OSSEC agent behind NAT

  - by Eric

  I am working on an OSSEC deployment where I will have multiple agents behind 1 public IP. Below is an example of the setup Private Network OSSEC-Agent1 (192.168.1.10) OSSEC-Agent2 (192.168.50.33) OSSEC-Agent3 (10.10.10.1) Those IPs NAT to 1 public IP (1.1.1.1) Then 1.1.1.1 talks to the public OSSEC server on 2.2.2.2 I've read some OSSEC documentation talking about NAT here, but it doesn't tell me exactly what I need to know. Their example is using an entire /24 subnet and mine will mainly have multiple agents to only 1 public IP. With the setup so far, I brought Agent1 online fine and it is communicating to the OSSEC server. However Agent2 continues to fail trying to connect to 2.2.2.2. Even though when I added the key, I had the correct name for it, so I know it talked to the portal at least once for that information. I'm assuming it's just getting confused with the multiple keys to 1 public IP. I basically want to know if this is possible and/or if I'm just overlooking something simple. Any help would be greatly appreciated.

  Read the article

• Is there a distributed project management software like Redmine?

  - by Tobias Kienzler

  I am quite familiar with and love using git, among other reasons due to its distributed nature. Now I'd like to set up some similarly distributed (FOSS) Project Management software with features similar to what Redmine offers, such as Issue & time tracking, milestones Gantt charts, calendar git integration, maybe some automatic linking of commits and issues Wiki (preferably with Mathjax support) Forum, news, notifications Multiple Projects However, I am looking for a solution that does not require a permanently accesible server, i.e. like in git, each user should have their own copy which can be easily synchronized with others. However it should be possible to not have a copy of every Project on every machine. Since trac uses multiple instances for multiple projects anyway, I was considering using that, but I neither know how well it adapts to simply giting the database itself (which would be be easiest way to handle the distribution due to git being used anyway), nor does it include all of Redmine's feature. So, can you recommend me a distributed project management software? If your suggestion is a software that usually runs on a server please include a description of the distribution method (e.g. whether simply putting the data in a git repository would do the trick), and if it's e.g. trac, please mention plugins required to include the features mentioned.

  Read the article

• Can Foswiki be used as a distributed Redmine replacement? [closed]

  - by Tobias Kienzler

  I am quite familiar with and love using git, among other reasons due to its distributed nature. Now I'd like to set up some similarly distributed (FOSS) Project Management software with features similar to what Redmine offers, such as Issue & time tracking, milestones Gantt charts, calendar git integration, maybe some automatic linking of commits and issues Wiki (preferably with Mathjax support) Forum, news, notifications Multiple Projects However, I am looking for a solution that does not require a permanently accesible server, i.e. like in git, each user should have their own copy which can be easily synchronized with others. However it should be possible to not have a copy of every Project on every machine. Since trac uses multiple instances for multiple projects anyway, I was considering using that, but I neither know how well it adapts to simply giting the database itself (which would be be easiest way to handle the distribution due to git being used anyway), nor does it include all of Redmine's feature. After checking http://www.wikimatrix.org for Wikis with integrated tracking system and RCS support, and filtering out seemingly stale project, the choices basically boil down to Foswiki, TWiki and Ikiwiki. The latter doesn't seem to offer as many usability features, and in the TWiki vs Foswiki issue I tend to the latter. Finally, there is Fossil, which starts from the other end by attempting to replace git entirely and tracking itself. I am however not too comfortable with the thought of replacing git, and Fossil's non-SCM features don't seem to be as developed. Now before I invest too much time when someone else might already have tried this, I basically have two questions: Are there crucial features of Project Management software like Redmine that Foswiki does not provide even with all the extensions available? How to set Foswiki up to use git instead of the perl RcsLite?

  Read the article

• Jump and run HTML5 Game Framework

  - by user1818924

  We're developing a jump and run game with HTML5 and JavaScript and have to build an own game framework for this. Here we have some difficulties and would like to ask you for some advice: we have a "Stage" object, which represents the root of our game and is a global div-wrapper. The stage can contain multiple "Scenes", which are also div-elements. We would implement a Scene for the playing task, for pause, etc. and switch between them. Each scene can therefore contain multiple "Layers", representing a canvas. These Layer contain "ObjectEntities", which represent images or other shapes like rectangles, etc. Each Objectentity has its own temporaryCanvas, to be able to draw images for one entity, whereas another contains a rectangle. We set an activeScene in our Stage, so when the game is played, just the active scene is drawn. Calling activeScene.draw(), calls all sublayers to draw, which draw their entities (calling drawImage(entity.canvas)). But is this some kind of good practive? Having multiple canvas to draw? Each gameloop every layer-context is cleared and drawn again. E.g. we just have a still Background-Layer, … wouldn't it be more useful to draw this once and not to clear it everytime and redraw it? Or should we use a global canvas for example in the Stage and just use this canvas to draw? But we thought this would be to expensive... Other question: Do you have any advice how we could dive into implementing an own framework? Most stuff we find online relies on existing frameworks or they just implement their game without building a framework.

  Read the article

• How Do I Print Photos?

  - by Takkat

  Other than for Windows in Ubuntu there are no fancy utilities provided from printer manufacturers to print photos. I am aware of Gnome Photo Printer and of Photoprint, the first being easy to handle, the latter having more options. However I wonder if there are any other or maybe even better alternatives (including plugins) to perform the following tasks: Print photos in the best photo-resolution the driver offers Adjust paper size for standard values of photo papers Choose paper tray if the printer has more than one Print out multiple photos on one page including mixed sizes (grids) Multiple prints with same settings Borderless printing if the printer is capable of this Any additional options like pre-processing for color correction or noise reduction would be nice to have but are not so essential. Update According to this spec it seems not to so easy to accomplish the simple task of printing photos. Indeed all applications I have gone through have major drawbacks that make printing photos almost impossible. Below I will list what put me off using them for photo printing: Gnome Photo Printer: no thumbnails, no grids Photoprint: does not keep settings, GUI broken, no standard photo size, no thumbs Eye Of Gnome: no multiple pages, no grids Gimp + Images Grid Layout: far too many steps to finally find that prints are always different to their previews. F-Spot: no grids Picasa 3: no grids, very few fixed paper sizes, 300 dpi only flPhoto: strange GUI, no thumbs, no printer settings, did not print at all Windows: Ooops - everything works fine! But I want Ubuntu to do this! After half a pack of ink cartridges and half a pack of photo paper cards I am getting tired of testing. At least Gimp and Picasa looked promising but both don't keep their promise when it comes to printing. I'd already be happy to quickly print a few photos with EOG if bug #80220 was fixed - but it's still on "wishlist".

  Read the article

• How do developers verify that software requirement changes in one system do not violate a requirement of downstream software systems?

  - by Peter Smith

  In my work, I do requirements gathering, analysis and design of business solutions in addition to coding. There are multiple software systems and packages, and developers are expected to work on any of them, instead of being assigned to make changes to only 1 system or just a few systems. How developers ensure they have captured all of the necessary requirements and resolved any conflicting requirements? An example of this type of scenario: Bob the developer is asked to modify the problem ticket system for a hypothetical utility repair business. They contract with a local utility company to provide this service. The old system provides a mechanism for an external customer to create a ticket indicating a problem with utility service at a particular address. There is a scheduling system and an invoicing system that is dependent on this data. Bob's new project is to modify the ticket placement system to allow for multiple addresses to entered by a landlord or other end customer with multiple properties. The invoicing system bills per ticket, but should be modified to bill per address. What practices would help Bob discover that the invoicing system needs to be changed as well? How might Bob discover what other systems in his company might need to be changed in order to support the new changes\business model? Let's say there is a documented specification for each system involved, but there are many systems and Bob is not familiar with all of them. End of example. We're often in this scenario, and we do have design reviews but management places ultimate responsibility for any defects (business process or software process) on the developer who is doing the design and the work. Some organizations seem to be better at this than others. How do they manage to detect and solve conflicting or incomplete requirements across software systems? We currently have a lot of tribal knowledge and just a few developers who understand the entire business and software chain. This seems highly ineffective and leads to problems at the requirements level.

  Read the article

• EM12c Release 4: Database as a Service Enhancements

  - by Adeesh Fulay

  Oracle Enterprise Manager 12.1.0.4 (or simply put EM12c R4) is the latest update to the product. As previous versions, this release provides tons of enhancements and bug fixes, attributing to improved stability and quality. One of the areas that is most exciting and has seen tremendous growth in the last few years is that of Database as a Service. EM12c R4 provides a significant update to Database as a Service. The key themes are: Comprehensive Database Service Catalog (includes single instance, RAC, and Data Guard) Additional Storage Options for Snap Clone (includes support for Database feature CloneDB) Improved Rapid Start Kits Extensible Metering and Chargeback Miscellaneous Enhancements 1. Comprehensive Database Service Catalog Before we get deep into implementation of a service catalog, lets first understand what it is and what benefits it provides. Per ITIL, a service catalog is an exhaustive list of IT services that an organization provides or offers to its employees or customers. Service catalogs have been widely popular in the space of cloud computing, primarily as the medium to provide standardized and pre-approved service definitions. There is already some good collateral out there that talks about Oracle database service catalogs. The two whitepapers i recommend reading are: Service Catalogs: Defining Standardized Database Service High Availability Best Practices for Database Consolidation: The Foundation for Database as a Service [Oracle MAA] EM12c comes with an out-of-the-box service catalog and self service portal since release 1. For the customers, it provides the following benefits: Present a collection of standardized database service definitions, Define standardized pools of hardware and software for provisioning, Role based access to cater to different class of users, Automated procedures to provision the predefined database definitions, Setup chargeback plans based on service tiers and database configuration sizes, etc Starting Release 4, the scope of services offered via the service catalog has been expanded to include databases with varying levels of availability - Single Instance (SI) or Real Application Clusters (RAC) databases with multiple data guard based standby databases. Some salient points of the data guard integration: Standby pools can now be defined across different datacenters or within the same datacenter as the primary (this helps in modelling the concept of near and far DR sites) The standby databases can be single instance, RAC, or RAC One Node databases Multiple standby databases can be provisioned, where the maximum limit is determined by the version of database software The standby databases can be in either mount or read only (requires active data guard option) mode All database versions 10g to 12c supported (as certified with EM 12c) All 3 protection modes can be used - Maximum availability, performance, security Log apply can be set to sync or async along with the required apply lag The different service levels or service tiers are popularly represented using metals - Platinum, Gold, Silver, Bronze, and so on. The Oracle MAA whitepaper (referenced above) calls out the various service tiers as defined by Oracle's best practices, but customers can choose any logical combinations from the table below:  Primary  Standby [1 or more]  EM 12cR4  SI  -  SI  SI  RAC -  RAC SI  RAC RAC  RON -  RON RON where RON = RAC One Node is supported via custom post-scripts in the service template A sample service catalog would look like the image below. Here we have defined 4 service levels, which have been deployed across 2 data centers, and have 3 standardized sizes. Again, it is important to note that this is just an example to get the creative juices flowing. I imagine each customer would come up with their own catalog based on the application requirements, their RTO/RPO goals, and the product licenses they own. In the screenwatch titled 'Build Service Catalog using EM12c DBaaS', I walk through the complete steps required to setup this sample service catalog in EM12c. 2. Additional Storage Options for Snap Clone In my previous blog posts, i have described the snap clone feature in detail. Essentially, it provides a storage agnostic, self service, rapid, and space efficient approach to solving your data cloning problems. The net benefit is that you get incredible amounts of storage savings (on average 90%) all while cloning databases in a matter of minutes. Space and Time, two things enterprises would love to save on. This feature has been designed with the goal of providing data cloning capabilities while protecting your existing investments in server, storage, and software. With this in mind, we have pursued with the dual solution approach of Hardware and Software. In the hardware approach, we connect directly to your storage appliances and perform all low level actions required to rapidly clone your databases. While in the software approach, we use an intermediate software layer to talk to any storage vendor or any storage configuration to perform the same low level actions. Thus delivering the benefits of database thin cloning, without requiring you to drastically changing the infrastructure or IT's operating style. In release 4, we expand the scope of options supported by snap clone with the addition of database CloneDB. While CloneDB is not a new feature, it was first introduced in 11.2.0.2 patchset, it has over the years become more stable and mature. CloneDB leverages a combination of Direct NFS (or dNFS) feature of the database, RMAN image copies, sparse files, and copy-on-write technology to create thin clones of databases from existing backups in a matter of minutes. It essentially has all the traits that we want to present to our customers via the snap clone feature. For more information on cloneDB, i highly recommend reading the following sources: Blog by Tim Hall: Direct NFS (DNFS) CloneDB in Oracle Database 11g Release 2 Oracle OpenWorld Presentation by Cern: Efficient Database Cloning using Direct NFS and CloneDB The advantages of the new CloneDB integration with EM12c Snap Clone are: Space and time savings Ease of setup - no additional software is required other than the Oracle database binary Works on all platforms Reduce the dependence on storage administrators Cloning process fully orchestrated by EM12c, and delivered to developers/DBAs/QA Testers via the self service portal Uses dNFS to delivers better performance, availability, and scalability over kernel NFS Complete lifecycle of the clones managed by EM12c - performance, configuration, etc 3. Improved Rapid Start Kits DBaaS deployments tend to be complex and its setup requires a series of steps. These steps are typically performed across different users and different UIs. The Rapid Start Kit provides a single command solution to setup Database as a Service (DBaaS) and Pluggable Database as a Service (PDBaaS). One command creates all the Cloud artifacts like Roles, Administrators, Credentials, Database Profiles, PaaS Infrastructure Zone, Database Pools and Service Templates. Once the Rapid Start Kit has been successfully executed, requests can be made to provision databases and PDBs from the self service portal. Rapid start kit can create complex topologies involving multiple zones, pools and service templates. It also supports standby databases and use of RMAN image backups. The Rapid Start Kit in reality is a simple emcli script which takes a bunch of xml files as input and executes the complete automation in a matter of seconds. On a full rack Exadata, it took only 40 seconds to setup PDBaaS end-to-end. This kit works for both Oracle's engineered systems like Exadata, SuperCluster, etc and also on commodity hardware. One can draw parallel to the Exadata One Command script, which again takes a bunch of inputs from the administrators and then runs a simple script that configures everything from network to provisioning the DB software. Steps to use the kit: The kit can be found under the SSA plug-in directory on the OMS: EM_BASE/oracle/MW/plugins/oracle.sysman.ssa.oms.plugin_12.1.0.8.0/dbaas/setup It can be run from this default location or from any server which has emcli client installed For most scenarios, you would use the script dbaas/setup/database_cloud_setup.py For Exadata, special integration is provided to reduce the number of inputs even further. The script to use for this scenario would be dbaas/setup/exadata_cloud_setup.py The database_cloud_setup.py script takes two inputs: Cloud boundary xml: This file defines the cloud topology in terms of the zones and pools along with host names, oracle home locations or container database names that would be used as infrastructure for provisioning database services. This file is optional in case of Exadata, as the boundary is well know via the Exadata system target available in EM. Input xml: This file captures inputs for users, roles, profiles, service templates, etc. Essentially, all inputs required to define the DB services and other settings of the self service portal. Once all the xml files have been prepared, invoke the script as follows for PDBaaS: emcli @database_cloud_setup.py -pdbaas -cloud_boundary=/tmp/my_boundary.xml -cloud_input=/tmp/pdb_inputs.xml          The script will prompt for passwords a few times for key users like sysman, cloud admin, SSA admin, etc. Once complete, you can simply log into EM as the self service user and request for databases from the portal. More information available in the Rapid Start Kit chapter in Cloud Administration Guide.  4. Extensible Metering and Chargeback  Last but not the least, Metering and Chargeback in release 4 has been made extensible in all possible regards. The new extensibility features allow customer, partners, system integrators, etc to : Extend chargeback to any target type managed in EM Promote any metric in EM as a chargeback entity Extend list of charge items via metric or configuration extensions Model abstract entities like no. of backup requests, job executions, support requests, etc  A slew of emcli verbs have also been added that allows administrators to create, edit, delete, import/export charge plans, and assign cost centers all via the command line. More information available in the Chargeback API chapter in Cloud Administration Guide. 5. Miscellaneous Enhancements There are other miscellaneous, yet important, enhancements that are worth a mention. These mostly have been asked by customers like you. These are: Custom naming of DB Services Self service users can provide custom names for DB SID, DB service, schemas, and tablespaces Every custom name is validated for uniqueness in EM 'Create like' of Service Templates Now creating variants of a service template is only a click away. This would be vital when you publish service templates to represent different database sizes or service levels. Profile viewer View the details of a profile like datafile, control files, snapshot ids, export/import files, etc prior to its selection in the service template Cleanup automation - for failed and successful requests Single emcli command to cleanup all remnant artifacts of a failed request Cleanup can be performed on a per request bases or by the entire pool As an extension, you can also delete successful requests Improved delete user workflow Allows administrators to reassign cloud resources to another user or delete all of them Support for multiple tablespaces for schema as a service In addition to multiple schemas, user can also specify multiple tablespaces per request I hope this was a good introduction to the new Database as a Service enhancements in EM12c R4. I encourage you to explore many of these new and existing features and give us feedback. Good luck! References: Cloud Management Page on OTN Cloud Administration Guide [Documentation] -- Adeesh Fulay (@adeeshf)

  Read the article

< Previous Page | 310 311 312 313 314 315 316 317 318 319 320 321  | Next Page >