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  • Designing Databases for Rapid Resilience

    As the volume of data increases, DBAs need to plan more actively for rapid restores in the event of failure. For this, the intelligent use of filegroups is important, particularly when the Enterprise Edition of SQL Server offers the hope of online restores. How, though, should you arrange your data on the different filegroups? What happenens if the primary filegroup gets corrupted? Why backup and restore indexes?

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  • Designing Databases for Rapid Resilience

    As the volume of data increases, DBAs need to plan more actively for rapid restores in the event of failure. For this, the intelligent use of filegroups is important, particularly when the Enterprise Edition of SQL Server offers the hope of online restores. How, though, should you arrange your data on the different filegroups? What happenens if the primary filegroup gets corrupted? Why backup and restore indexes?

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  • Handling Backups for Rapid Resilience

    The backup and restore system in SQL Server hasn't changed a great deal over the years despite a huge growth in the typical size of databases. When disaster strikes, and an important service is taken offline while a restore is performed, there is often time to reflect on whether it might be possible to design databases for a more rapid recovery of the most critical parts of a database application. Uncover the flexibility of custom metricsKeep up to date from anywhere with SQL Monitor, and monitor the most important data for your servers and applications. Download a free trial.

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  • MSMQ Resilience

    - by Paddy Carroll
    I have a requirement for a resilient MSMQ setup on VMWare ESX5. I am aware that we cannot allow the queue storage to be shared as it must be installed on physical disk mount, e.g. it cant be an CIFS or DFS Share. The following constraints apply: We don't use windows clustering We dont't rely on hot standbys Is there a way I can replicate the queue storage to another platform so that it can assume MSMQ duties on failure of the primary platforms using any method including queue forwarding?

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  • How do we keep Active Directory resilient across multiple sites?

    - by Alistair Bell
    I handle much of the IT for a company of around 100 people, spread across about five sites worldwide. We're using Active Directory for authentication, mostly served to Linux (CentOS 5) systems via LDAP. We've been suffering through a spate of events where the IP tunnel between the two major sites goes down and the secondary domain controller at one site can't contact the primary domain controller at the other. It seems that the secondary domain controller starts denying user authentication within minutes of losing connectivity to the primary. How do we make the secondary domain controller more resilient to downtime? Is there a way for it to cache the entire directory and/or at least keep enough information locally to survive a multi-hour disconnection? (We're all in a single organizational unit if that makes any difference.) (The servers here are Windows Server 2003; don't assume that we set this up correctly. I'm a software engineer, not an IT specialist.)

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  • BizTalk Server 2009 - Architecture Options

    - by StuartBrierley
    I recently needed to put forward a proposal for a BizTalk 2009 implementation and as a part of this needed to describe some of the basic architecture options available for consideration.  While I already had an idea of the type of environment that I would be looking to recommend, I felt that presenting a range of options while trying to explain some of the strengths and weaknesses of those options was a good place to start.  These outline architecture options should be equally valid for any version of BizTalk Server from 2004, through 2006 and R2, up to 2009.   The following diagram shows a crude representation of the common implementation options to consider when designing a BizTalk environment.         Each of these options provides differing levels of resilience in the case of failure or disaster, with the later options also providing more scope for performance tuning and scalability.   Some of the options presented above make use of clustering. Clustering may best be described as a technology that automatically allows one physical server to take over the tasks and responsibilities of another physical server that has failed. Given that all computer hardware and software will eventually fail, the goal of clustering is to ensure that mission-critical applications will have little or no downtime when such a failure occurs. Clustering can also be configured to provide load balancing, which should generally lead to performance gains and increased capacity and throughput.   (A) Single Servers   This option is the most basic BizTalk implementation that should be considered. It involves the deployment of a single BizTalk server in conjunction with a single SQL server. This configuration does not provide for any resilience in the case of the failure of either server. It is however the cheapest and easiest to implement option of those available.   Using a single BizTalk server does not provide for the level of performance tuning that is otherwise available when using more than one BizTalk server in a cluster.   The common edition of BizTalk used in single server implementations is the standard edition. It should be noted however that if future demand requires increased capacity for a solution, this BizTalk edition is limited to scaling up the implementation and not scaling out the number of servers in use. Any need to scale out the solution would require an upgrade to the enterprise edition of BizTalk.   (B) Single BizTalk Server with Clustered SQL Servers   This option uses a single BizTalk server with a cluster of SQL servers. By utilising clustered SQL servers we can ensure that there is some resilience to the implementation in respect of the databases that BizTalk relies on to operate. The clustering of two SQL servers is possible with the standard edition but to go beyond this would require the enterprise level edition. While this option offers improved resilience over option (A) it does still present a potential single point of failure at the BizTalk server.   Using a single BizTalk server does not provide for the level of performance tuning that is otherwise available when using more than one BizTalk server in a cluster.   The common edition of BizTalk used in single server implementations is the standard edition. It should be noted however that if future demand requires increased capacity for a solution, this BizTalk edition is limited to scaling up the implementation and not scaling out the number of servers in use. You are also unable to take advantage of multiple message boxes, which would allow us to balance the SQL load in the event of any bottlenecks in this area of the implementation. Any need to scale out the solution would require an upgrade to the enterprise edition of BizTalk.   (C) Clustered BizTalk Servers with Clustered SQL Servers   This option makes use of a cluster of BizTalk servers with a cluster of SQL servers to offer high availability and resilience in the case of failure of either of the server types involved. Clustering of BizTalk is only available with the enterprise edition of the product. Clustering of two SQL servers is possible with the standard edition but to go beyond this would require the enterprise level edition.    The use of a BizTalk cluster also provides for the ability to balance load across the servers and gives more scope for performance tuning any implemented solutions. It is also possible to add more BizTalk servers to an existing cluster, giving scope for scaling out the solution as future demand requires.   This might be seen as the middle cost option, providing a good level of protection in the case of failure, a decent level of future proofing, but at a higher cost than the single BizTalk server implementations.   (D) Clustered BizTalk Servers with Clustered SQL Servers – with disaster recovery/service continuity   This option is similar to that offered by (C) and makes use of a cluster of BizTalk servers with a cluster of SQL servers to offer high availability and resilience in case of failure of either of the server types involved. Clustering of BizTalk is only available with the enterprise edition of the product. Clustering of two SQL servers is possible with the standard edition but to go beyond this would require the enterprise level edition.    As with (C) the use of a BizTalk cluster also provides for the ability to balance load across the servers and gives more scope for performance tuning the implemented solution. It is also possible to add more BizTalk servers to an existing cluster, giving scope for scaling the solution out as future demand requires.   In this scenario however, we would be including some form of disaster recovery or service continuity. An example of this would be making use of multiple sites, with the BizTalk server cluster operating across sites to offer resilience in case of the loss of one or more sites. In this scenario there are options available for the SQL implementation depending on the network implementation; making use of either one cluster per site or a single SQL cluster across the network. A multi-site SQL implementation would require some form of data replication across the sites involved.   This is obviously an expensive and complex option, but does provide an extraordinary amount of protection in the case of failure.

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  • Cost Comparison Hard Disk Drive to Solid State Drive on Price per Gigabyte - dispelling a myth!

    - by tonyrogerson
    It is often said that Hard Disk Drive storage is significantly cheaper per GiByte than Solid State Devices – this is wholly inaccurate within the database space. People need to look at the cost of the complete solution and not just a single component part in isolation to what is really required to meet the business requirement. Buying a single Hitachi Ultrastar 600GB 3.5” SAS 15Krpm hard disk drive will cost approximately £239.60 (http://scan.co.uk, 22nd March 2012) compared to an OCZ 600GB Z-Drive R4 CM84 PCIe costing £2,316.54 (http://scan.co.uk, 22nd March 2012); I’ve not included FusionIO ioDrive because there is no public pricing available for it – something I never understand and personally when companies do this I immediately think what are they hiding, luckily in FusionIO’s case the product is proven though is expensive compared to OCZ enterprise offerings. On the face of it the single 15Krpm hard disk has a price per GB of £0.39, the SSD £3.86; this is what you will see in the press and this is what sales people will use in comparing the two technologies – do not be fooled by this bullshit people! What is the requirement? The requirement is the database will have a static size of 400GB kept static through archiving so growth and trim will balance the database size, the client requires resilience, there will be several hundred call centre staff querying the database where queries will read a small amount of data but there will be no hot spot in the data so the randomness will come across the entire 400GB of the database, estimates predict that the IOps required will be approximately 4,000IOps at peak times, because it’s a call centre system the IO latency is important and must remain below 5ms per IO. The balance between read and write is 70% read, 30% write. The requirement is now defined and we have three of the most important pieces of the puzzle – space required, estimated IOps and maximum latency per IO. Something to consider with regard SQL Server; write activity requires synchronous IO to the storage media specifically the transaction log; that means the write thread will wait until the IO is completed and hardened off until the thread can continue execution, the requirement has stated that 30% of the system activity will be write so we can expect a high amount of synchronous activity. The hardware solution needs to be defined; two possible solutions: hard disk or solid state based; the real question now is how many hard disks are required to achieve the IO throughput, the latency and resilience, ditto for the solid state. Hard Drive solution On a test on an HP DL380, P410i controller using IOMeter against a single 15Krpm 146GB SAS drive, the throughput given on a transfer size of 8KiB against a 40GiB file on a freshly formatted disk where the partition is the only partition on the disk thus the 40GiB file is on the outer edge of the drive so more sectors can be read before head movement is required: For 100% sequential IO at a queue depth of 16 with 8 worker threads 43,537 IOps at an average latency of 2.93ms (340 MiB/s), for 100% random IO at the same queue depth and worker threads 3,733 IOps at an average latency of 34.06ms (34 MiB/s). The same test was done on the same disk but the test file was 130GiB: For 100% sequential IO at a queue depth of 16 with 8 worker threads 43,537 IOps at an average latency of 2.93ms (340 MiB/s), for 100% random IO at the same queue depth and worker threads 528 IOps at an average latency of 217.49ms (4 MiB/s). From the result it is clear random performance gets worse as the disk fills up – I’m currently writing an article on short stroking which will cover this in detail. Given the work load is random in nature looking at the random performance of the single drive when only 40 GiB of the 146 GB is used gives near the IOps required but the latency is way out. Luckily I have tested 6 x 15Krpm 146GB SAS 15Krpm drives in a RAID 0 using the same test methodology, for the same test above on a 130 GiB for each drive added the performance boost is near linear, for each drive added throughput goes up by 5 MiB/sec, IOps by 700 IOps and latency reducing nearly 50% per drive added (172 ms, 94 ms, 65 ms, 47 ms, 37 ms, 30 ms). This is because the same 130GiB is spread out more as you add drives 130 / 1, 130 / 2, 130 / 3 etc. so implicit short stroking is occurring because there is less file on each drive so less head movement required. The best latency is still 30 ms but we have the IOps required now, but that’s on a 130GiB file and not the 400GiB we need. Some reality check here: a) the drive randomness is more likely to be 50/50 and not a full 100% but the above has highlighted the effect randomness has on the drive and the more a drive fills with data the worse the effect. For argument sake let us assume that for the given workload we need 8 disks to do the job, for resilience reasons we will need 16 because we need to RAID 1+0 them in order to get the throughput and the resilience, RAID 5 would degrade performance. Cost for hard drives: 16 x £239.60 = £3,833.60 For the hard drives we will need disk controllers and a separate external disk array because the likelihood is that the server itself won’t take the drives, a quick spec off DELL for a PowerVault MD1220 which gives the dual pathing with 16 disks 146GB 15Krpm 2.5” disks is priced at £7,438.00, note its probably more once we had two controller cards to sit in the server in, racking etc. Minimum cost taking the DELL quote as an example is therefore: {Cost of Hardware} / {Storage Required} £7,438.60 / 400 = £18.595 per GB £18.59 per GiB is a far cry from the £0.39 we had been told by the salesman and the myth. Yes, the storage array is composed of 16 x 146 disks in RAID 10 (therefore 8 usable) giving an effective usable storage availability of 1168GB but the actual storage requirement is only 400 and the extra disks have had to be purchased to get the  IOps up. Solid State Drive solution A single card significantly exceeds the IOps and latency required, for resilience two will be required. ( £2,316.54 * 2 ) / 400 = £11.58 per GB With the SSD solution only two PCIe sockets are required, no external disk units, no additional controllers, no redundant controllers etc. Conclusion I hope by showing you an example that the myth that hard disk drives are cheaper per GiB than Solid State has now been dispelled - £11.58 per GB for SSD compared to £18.59 for Hard Disk. I’ve not even touched on the running costs, compare the costs of running 18 hard disks, that’s a lot of heat and power compared to two PCIe cards!Just a quick note: I've left a fair amount of information out due to this being a blog! If in doubt, email me :)I'll also deal with the myth that SSD's wear out at a later date as well - that's just way over done still, yes, 5 years ago, but now - no.

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  • On the art of self-promotion

    - by Tony Davis
    I attended Brent Ozar's Building the Fastest SQL Servers session at Tech Ed last week, and found myself engulfed in a 'perfect storm' of excellent technical and presentational skills coupled with an astute awareness of the value of promoting one's work. I spend a lot of time at such events talking to developers and DBAs about the value of blogging and writing articles, and my impression is that some could benefit from a touch less modesty and a little more self-promotion. I sense a reticence in many would-be writers. Is what I have to say important enough? Haven't far more qualified and established commentators, MVPs and so on, already said it? While it's a good idea to pick reasonably fresh and interesting topics, it's more important not to let such fears lead to writer's block. In the eyes of any future employer, your published writing is an extension of your resume. They will not care that a certain MVP knows how to solve problem x, but they will be very interested to see that you have tackled that same problem, and solved it in your own way, and described the process in your own voice. In your current job, your writing is one of the ways you can express to your peers, and to the organization as a whole, the value of what you contribute. Many Developers and DBAs seem to rely on the idea that their work will speak for itself, and that their skill shines out from it. Unfortunately, this isn't always true. Many Development DBAs, for example, will be painfully aware of the massive effort involved in tuning and adding resilience to rapidly developed applications. However, others in the organization who are unaware of what's involved in getting an application that is 'done' ready for production may dismiss such efforts as fussiness or conservatism. At the dark end of the development cycle, chickens come home to roost, but their droppings tend to land on those trying to clear up the mess. My advice is this: next time you fix a bug or improve the resilience or performance of a database or application, make sure that you use team meetings, informal discussions and so on to ensure that people understand what the problem was and what you had to do to fix it. Use your blog to describe, generally, the process you adopted, the resources you used and the insights that came from your work. Encourage your colleagues to do the same. By spreading the art of self-promotion to everyone involved in an IT project, we get a better idea of the extent of the work and the value of the contribution of all the team members. As always, we'd love to hear what you think. This very week, Simple-talk launches its new blogging platform. If any of this has moved you to 'throw your hat into the ring', drop us a mail at [email protected]. Cheers, Tony.

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  • On the art of self-promotion

    - by Tony Davis
    I attended Brent Ozar’s Building the Fastest SQL Servers session at Tech Ed last week, and found myself engulfed in a ‘perfect storm’ of excellent technical and presentational skills coupled with an astute awareness of the value of promoting one’s work. I spend a lot of time at such events talking to developers and DBAs about the value of blogging and writing articles, and my impression is that some could benefit from a touch less modesty and a little more self-promotion. I sense a reticence in many would-be writers. Is what I have to say important enough? Haven’t far more qualified and established commentators, MVPs and so on, already said it? While it’s a good idea to pick reasonably fresh and interesting topics, it’s more important not to let such fears lead to writer’s block. In the eyes of any future employer, your published writing is an extension of your resume. They will not care that a certain MVP knows how to solve problem x, but they will be very interested to see that you have tackled that same problem, and solved it in your own way, and described the process in your own voice. In your current job, your writing is one of the ways you can express to your peers, and to the organization as a whole, the value of what you contribute. Many Developers and DBAs seem to rely on the idea that their work will speak for itself, and that their skill shines out from it. Unfortunately, this isn’t always true. Many Development DBAs, for example, will be painfully aware of the massive effort involved in tuning and adding resilience to rapidly developed applications. However, others in the organization who are unaware of what’s involved in getting an application that is ‘done’ ready for production may dismiss such efforts as fussiness or conservatism. At the dark end of the development cycle, chickens come home to roost, but their droppings tend to land on those trying to clear up the mess. My advice is this: next time you fix a bug or improve the resilience or performance of a database or application, make sure that you use team meetings, informal discussions and so on to ensure that people understand what the problem was and what you had to do to fix it. Use your blog to describe, generally, the process you adopted, the resources you used and the insights that came from your work. Encourage your colleagues to do the same. By spreading the art of self-promotion to everyone involved in an IT project, we get a better idea of the extent of the work and the value of the contribution of all the team members. As always, we’d love to hear what you think. This very week, Simple-talk launches its new blogging platform. If any of this has moved you to ‘throw your hat into the ring’, drop us a mail at [email protected]. Cheers, Tony.

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  • On the art of self-promotion

    - by Tony Davis
    I attended Brent Ozar's Building the Fastest SQL Servers session at Tech Ed last week, and found myself engulfed in a 'perfect storm' of excellent technical and presentational skills coupled with an astute awareness of the value of promoting one's work. I spend a lot of time at such events talking to developers and DBAs about the value of blogging and writing articles, and my impression is that some could benefit from a touch less modesty and a little more self-promotion. I sense a reticence in many would-be writers. Is what I have to say important enough? Haven't far more qualified and established commentators, MVPs and so on, already said it? While it's a good idea to pick reasonably fresh and interesting topics, it's more important not to let such fears lead to writer's block. In the eyes of any future employer, your published writing is an extension of your resume. They will not care that a certain MVP knows how to solve problem x, but they will be very interested to see that you have tackled that same problem, and solved it in your own way, and described the process in your own voice. In your current job, your writing is one of the ways you can express to your peers, and to the organization as a whole, the value of what you contribute. Many Developers and DBAs seem to rely on the idea that their work will speak for itself, and that their skill shines out from it. Unfortunately, this isn't always true. Many Development DBAs, for example, will be painfully aware of the massive effort involved in tuning and adding resilience to rapidly developed applications. However, others in the organization who are unaware of what's involved in getting an application that is 'done' ready for production may dismiss such efforts as fussiness or conservatism. At the dark end of the development cycle, chickens come home to roost, but their droppings tend to land on those trying to clear up the mess. My advice is this: next time you fix a bug or improve the resilience or performance of a database or application, make sure that you use team meetings, informal discussions and so on to ensure that people understand what the problem was and what you had to do to fix it. Use your blog to describe, generally, the process you adopted, the resources you used and the insights that came from your work. Encourage your colleagues to do the same. By spreading the art of self-promotion to everyone involved in an IT project, we get a better idea of the extent of the work and the value of the contribution of all the team members. As always, we'd love to hear what you think. This very week, Simple-talk launches its new blogging platform. If any of this has moved you to 'throw your hat into the ring', drop us a mail at [email protected]. Cheers, Tony.

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  • links for 2010-06-14

    - by Bob Rhubart
    White Paper: Application Portfolio Rationalization: How IT Standardization Fuels Growth Co-authors Hamidou Dia and Roy Hunter describe an Enterprise Architecture approach to application portfolio rationalization. (tags: oracle otn entarch) @soatoday: Cloud & Compliance: Write a Solid Prenup "Think of your cloud contract as a prenuptial agreement," says Oracle ACE Director Jordan Braunstein. "There must be clear recourse and commitments." (tags: soa cloud oracleace entarch) @fteter: Resilience and Relationships "Take a look at your own enterprise architecture with these ideas in mind," suggests Oracle ACE Director Floyd Teter, "and see if your outlook doesn't change." (tags: entarch complexity oracleace) @lucasjellema: Calling an EJB from a SOA Composite Application using the EJB Binding based on Java Interface Oracle ACE Director Lucas Jellema illustrates the use of one of several new capabilities in Oracle SOA Suite 11g R1 Patch Set 2 (11.1.1.3.0). (tags: soa oracleace middleware soasuite oracle)

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  • Free WebLogic Administration Cookbook

    - by Antony Reynolds
    Free WebLogic Admin Cookbook Packt Publishing are offering free copies of Oracle WebLogic Server 12c Advanced Administration Cookbook : http://www.packtpub.com/oracle-weblogic-server-12c-advanced-administration-cookbook/book  in exchange for a review either on your blog or on the title’s Amazon page. Here’s the blurb: Install, create and configure WebLogic Server Configure an Administration Server with high availability Create and configure JDBC data sources, multi data sources and gridlink data sources Tune the multi data source to survive database failures Setup JMS distributed queues Use WLDF to send threshold notifications Configure WebLogic Server for stability and resilience If you’re a datacenter operator, system administrator or even a Java developer this book could be exactly what you are looking for to take you one step further with Oracle WebLogic Server, this is a good way to bag yourself a free cookbook (current retail price $25.49). Free review copies are available until Tuesday 2nd July 2013, so if you are interested, email Harleen Kaur Bagga at: harleenb-AT-packtpub.com. I will be posting my own review shortly!

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  • Live Webcast: Private Cloud Database Consolidation with Oracle Exadata

    - by kimberly.billings
    Thursday, January 20th, 2011 at 9:00 am PT In this webcast, you'll learn how Oracle Exadata, Oracle Database 11g, and Oracle Real Application Clusters enable you to consolidate multiple applications on clustered server and storage pools to achieve extreme performance and lower your IT costs. You'll also learn how to maximize the efficiencies of private clouds, including: • Multitenancy • Rapid provisioning • Pay-for-use infrastructure Join us for this live Webcast and discover how Oracle Exadata delivers key cloud capabilities, providing elastic database services that can be quickly provisioned on demand. Register today! To learn more about how customers are consolidating on private clouds with Exadata, watch this video about how Commonwealth Bank of Australia consolidated multiple database services, including OLTP applications such as PeopleSoft Financials, onto an Exadata platform for improved performance and resilience and faster time-to-market.

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  • What would be the optimal disk config for SQL Server 2008 R2?

    - by Kev
    We have a new Dell R710 server that came with the following storage configuration: 8 x 146GB SAS 10k 6Gbps disks 1 x Perc H700 Integrated Controller (2 x 4 disks - 2 ports each supporting 4 disks) What would be the optimal configuration if we were just after performance? What would be the optimal configuration if we were after performance but wanted data resilience. As per 2 above but with a hot standby disk? We plan to run Windows 2008 R2 and SQL Server 2008 R2. Maximising storage capacity isn't a prime concern.

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  • Shopping for Fast USB Flash Drives

    - by Jim McKeeth
    I would like to pick up some really fast USB flash drives in the 16 - 64 GB range. When looking at drives they just list their size, their form factor (key chain hook, slider, etc.) and the fact that they are all Hi-Speed USB 2.0. It seems like I have heard that different drives have different performance and life expectancy. The sales guy tells me that they are all the same performance any more, but it wouldn't be the first time a sales guy had the wrong technical details. Our objective is to run Virtual PC images off of them, so good speed and resilience to rewrites it important.

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  • Possible to use DRBD on two ESXi virtualized servers?

    - by chen
    I have two servers (attached disks have been set up as hardware RAID1 for disk device level failure resilience). Here is the setup in my mind: 1) Install ESXi on each of the physical server, M1, M2; 2) Start one VM on each of the ESXi virtualized physical server V1, V2; 3) Install the DRDB drivers within V1 and V2. Essentially, this is a "virtualizing machine running DRBD in the VM's instead of bare metal hardware" idea. My question is whether the above setup can achieve the same "networked RAID1" goal that DRDB can achieve in the bare-metal physical machines (http://www.drbd.org/). Thanks. [EDIT] I found this (http://serverfault.com/questions/49305/drbd-experimentation-and-virtualization) is a similar question, but the answer does not seem to be firmative enough for me to follow.

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  • Should I never put a transactional replication distributor on a subscriber server?

    - by Stuart Branham
    What factors into choosing a distribution server for transactional replication? In our topology, we've always had the distributor reside on the publishing server. We rarely generate snapshots and performance is good enough, so this is okay for us today. One of our instances is moving to a cluster, so we need to move the distributor off for resilience/symmetry. Right now our two choices are to use a server physically close to the publishers, or our single subscription server. Our publisher is in our main office, and our subscriber is in a colocation facility off-site which our ISP runs. We have a pretty good line to it. The reason we're even considering the latter is to save work and licensing costs.

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  • Obtain all keys of a Neo4j index

    - by MattiSG
    I have a Neo4j database whose content is generated dynamically from a big dataset. All “entry points” nodes are indexed on a named index (IndexManager.forNodes(…)). I can therefore look up a particular “entry point” node. However, I would now like to enumerate all those specific nodes, but I can't know on which key they were indexed. Is there any way to enumerate all keys of a Neo4j Index? If not, what would be the best way to store those keys, a data type that is eminently non-graph-oriented? UPDATE (thanks for asking details :) ): the list would be more than 2 million entries. The main use case would be to never update it after an initialization step, but other use cases might need it, so it has to be somewhat scalable. Also, I would really prefer avoiding killing my current resilience abilities, so storing all keys at once, as opposed to adding them incrementally, would be a last-resort solution.

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  • June Oracle Technology Network NEW Member Benefits - books books and more books!!!

    - by Cassandra Clark
    As we mentioned a few posts ago we are working to bring Oracle Technology Network members NEW benefits each month. Listed below are several discounts on technology books brought to you by Apress, Pearson, CRC Press and Packt Publishing. Happy reading!!! Apress Offers - Get 50% off the eBook below using promo code ORACLEJUNEJCCF. Pro ODP.NET for Oracle Database 11g By Edmund T. Zehoo This book is a comprehensive and easy-to-understand guide for using the Oracle Data Provider (ODP) version 11g on the .NET Framework. It also outlines the core GoF (Gang of Four) design patterns and coding techniques employed to build and deploy high-impact mission-critical applications using advanced Oracle database features through the ODP.NET provider. Pearson Offers - Get 35% off all titles listed below using code OTNMEMBER. SOA Design Patterns | Thomas Earl | ISBN: 0136135161 In cooperation with experts and practitioners throughout the SOA community, best-selling author Thomas Erl brings together the de facto catalog of design patterns for SOA and service-orientation. Oracle Performance Survival Guide | Guy Harrison | ISBN: 9780137011957 The fast, complete, start-to-finish guide to optimizing Oracle performance. Core JavaServer Faces, Third Edition | David Geary and Cay S. Horstmann | ISBN: 9780137012893 Provides everything you need to master the powerful and time-saving features of JSF 2.0? Solaris Security Essentials | ISBN: 9780137012336 A superb guide to deploying and managing secure computer environments.? Effective C#, Second Edition | Bill Wagner | ISBN: 9780321658708 Respected .NET expert Bill Wagner identifies fifty ways you can leverage the full power of the C# 4.0 language to express your designs concisely and clearly. CRC Press Offers - Use 813DA to get 20% off this the title below. Secure and Resilient Software Development This book illustrates all phases of the secure software development life cycle. It details quality software development strategies that stress resilience requirements with precise, actionable, and ground-level inputs. Packt Publishing Offers - Use the promo code "Java35June", to save 35% off of each eBook mentioned below. JSF 2.0 Cookbook By Anghel Leonard ISBN: 978-1-847199-52-2 Packed with fast, practical solutions and techniques for JavaServer Faces developers who want to push past the JSF basics. JavaFX 1.2 Application Development Cookbook By Vladimir Vivien ISBN: 978-1-847198-94-5 Fast, practical solutions and techniques for building powerful, responsive Rich Internet Applications in JavaFX.

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  • Has anyone used the sharedband connection bonding product?

    - by John Rennie
    See http://www.sharedband.com/ for details on the product. Obviously Sharedband aren't too keen on giving away their technical secrets, but I would guess that it bonds the connections at the IP layer i.e. their routers send the IP packets to the SharedBand routers over all available lines and the ShareBand routers handle all the virtual circuitry and provide the NATing to whatever IP address(es) they've assigned you. It looks a clever idea, and a good way to provide some resilience over ADSL links. You can even use ADSL links from different ISPs and SharedBand will still bond them for you. But, I find myself wondering how well it really works, and whether it's worth it. The Draytek routers can already load balance (though not bond) up to four ADSL lines, so the SharedBand product really only offers an advantage if you're hosting servers i.e. you can have one IP address to accept incoming connections through all your (working) ADSL lines. But should you really try and host servers using ADSL lines, especially since ADSL upload performance isn't stellar? Wouldn't it be better to use a hosted server, or maybe pay up for a leased line with a SLA? So I'm asking if anyone is using SharedBand, and if so what do you think of it? JR

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  • Using mixed disks and OpenFiler to create RAID storage

    - by Cylindric
    I need to improve my home storage to add some resilience. I currently have four disks, as follows: D0: 500Gb (System, Boot) D1: 1Tb D2: 500Gb D3: 250Gb There's a mix of partitions on there, so it's not JBOD, but data is pretty spread out and not redundant. As this is my primary PC and I don't want to give up the entire OS to storage, my plan is to use OpenFiler in a VM to create a virtual SAN. I will also use Windows Software RAID to mirror the OS. Partitions will be created as follows: D0 P1: 100Mb: System-Reserved Boot D0 P2: 50Gb: Virtual Machine VMDKs for OS D0 P3: 350Gb: Data D1 P1: 100Mb: System-Reserved Boot D1 P2: 50Gb: Virtual Machine VMDKs for OS D1 P3: 800Gb: Data D2 P1: 450Gb: Data D3 P1: 200Gb: Data This will result in: Mirrored boot partition Mirrored Operating system Mirrored Virtual machine O/S disks Four partitions for data In the four data partitions I will create several large VMDK files, which I will "mount" into OpenFiler as block-storage devices, combined into three RAID arrays (due to the differing disk sizes) In effect, I'll end up with the following usable partitions SYSTEM 100Mb the small boot partition created by the Windows 7 installer (RAID-1) HOST 50Gb the Windows 7 partition (RAID-1) GUESTS 50Gb Virtual machine Guest VMDK's (RAID-1) VG1 900Gb Volume group consisting of a RAID-5 and two RAID-1 VG2 300Gb Volume group consisting of a single disk On VG1 I can dynamically assign storage for my media, photographs, documents, whatever, and it will be safe. On VG2 I can dynamically assign storage for my data that is not critical, and easily recoverable, as it is not safe. Are there any particular 'gotchas' when implementing a virtual OpenFiler like this? Is the recovery process for a failing disk going to be very problematic? Thanks.

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  • BGP Multihomed/Multi-location best practice

    - by Tom O'Connor
    We're in the process of designing a new iteration of our network where we improve resilliency by adding a second datacentre. We'll be adding a second datacentre, with an identical configuration of servers as our primary location. To achieve network connectivity, we're looking into a couple of possible methods. See earlier questions http://serverfault.com/questions/86736/best-way-to-improve-resilience and http://serverfault.com/questions/101582/dns-round-robin-failover-and-load-balancing I'm pretty convinced that BGP is the right way to go about this, and this question is not about RRDNS. 1) If we have 2 locations, do we announce the same IP address block from both locations? 2) If we did this, but had a management ssh interface on x.x.x.50 from datacentre A, but it was on x.x.x.150 in datacentre B. What is the best practice mechanism for achieving this? Because if I were nearest to A, then all my traffic would go to x.50, but if i attempted to connect to x.150, I'd not be able to connect, because this address wouldn't be valid at A, but only at B. Is the best solution to announce 2 different netblocks, one at each location, facilitating the need for RRDNS, or to announce a single block, and run some form of VPN between the two sites for managment traffic?

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  • SQL Saturday and Exploring Data Privacy

    - by Johnm
    I have been highly impressed with the growth of the SQL Saturday phenomenon. It seems that an announcement for a new wonderful event finds its way to my inbox on a daily basis. I have had the opportunity to attend the first of the SQL Saturday's for Tampa, Chicago, Louisville and recently my home town of Indianapolis. It is my hope that there will be many more in my future. This past weekend I had the honor of being selected to speak amid a great line up of speakers at SQL Saturday #82 in Indianapolis. My session topic/title was "Exploring Data Privacy". Below is a brief synopsis of my session: Data Privacy in a Nutshell        - Definition of data privacy        - Examples of personally identifiable data        - Examples of Sensitive data Laws and Stuff        - Various examples of laws, regulations and policies that influence the definition of data privacy        - General rules of thumb that encompasses most laws Your Data Footprint        - Who has personal information about you?        - What are you exchanging data privacy for?        - The amazing resilience of data        - The cost of data loss Weapons of Mass Protection       - Data classification       - Extended properties       - Database Object Schemas       - An extraordinarily brief introduction of encryption       - The amazing data professional  <-the most important point of the entire session! The subject of data privacy is one that is quickly making its way to the forefront of the mind of many data professionals. Somewhere out there someone is storing personally identifiable and other sensitive data about you. In some cases it is kept reasonably secure. In other cases it is kept in total exposure without the consideration of its potential of damage to you. Who has access to it and how is it being used? Are we being unnecessarily required to supply sensitive data in exchange for products and services? These are just a few questions on everyone's mind. As data loss events of grand scale hit the headlines in a more frequent succession, the level of frustration and urgency for a solution increases. I assembled this session with the intent to raise awareness of sensitive data and remind us all that we, data professionals, are the ones who have the greatest impact and influence on how sensitive data is regarded and protected. Mahatma Gandhi once said "Be the change you want to see in the world." This is guidance that I keep near to my heart as I approached this topic of data privacy.

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  • When things go awry

    - by Phil Factor
    The moment the Entrepreneur opened his mouth on prime-time national TV, spelled out the URL and waxed big on how exciting ‘his’ new website was, I knew I was in for a busy night. I’d designed and built it. All at once, half a million people tried to log into the website. Although all my stress-testing paid off, I have to admit that the network locked up tight long before there was any danger of a database or website problem. Soon afterwards, the Entrepreneur and the Big Boss were there in the autopsy meeting. We picked through all our systems in detail to see how they’d borne the unexpected strain. Mercifully, in view of the sour mood of the Big Boss, it turned out that the only thing we could have done better was buy a bigger pipe to and from the internet. We’d specified that ‘big pipe’ when designing the system. The Big Boss had then railed at the cost and so we’d subsequently compromised. I felt that my design decisions were vindicated. The Big Boss brooded for a while. Then he made the significant comment: “What really ****** me off is the fact that, for ten minutes, we couldn’t take people’s money.” At that point I stopped feeling smug. Had the internet connection been better, the system would have reached its limit and failed rather precipitously, and that wasn’t what he wanted. Then it occurred to me that what had gummed up the connection was all those images on the site, that had made it so impressive for the visitors. If there had been a way to automatically pare down the site to the bare essentials under stress… Hmm. I began to consider disaster-recovery in the broadest sense – maintaining a service in spite of unusual or unexpected events. What he said makes a lot of sense: sacrifice whatever isn’t essential to keep the core service running when we approach the capacity limits. Maybe in IT we should borrow (or revive) the business concept of the ‘Skeleton service’, maintaining only the priority parts under stress, using a process that is well-prepared and carefully rehearsed. How might this work? Whatever the event we have to prepare for, it is all about understanding the priorities; knowing what one can dispense with when the going gets tough. In the event of database disaster, it’s much faster to deploy a skeletal system with only the essential data than to restore the entire system, though there would have to be a reconciliation process to update the revived database retrospectively, once the emergency was over. It isn’t just the database that could be designed for resilience. One could prepare for unusually high traffic in a website by designing a system that degraded gradually to a ‘skeletal’ site, one that maintained the commercial essentials without fat images, JavaScript libraries and razzmatazz. This is all what the Big Boss scathingly called ‘a mere technicality’. It seems to me that what is needed first is a culture of application and database design which acknowledges that we live in a very imperfect world, and react accordingly when things go awry.

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  • Maintain order of messages via proxies to app servers

    - by David Turner
    Hi, I am receiving messages from a 3rd party via a http post, and it is important that the order the messages hit our infrastructure is maintained through the load balancers and proxies until it hits our application server. Quick Diagram. (proxies in place due to security requirements.) [ACE load balancer] - [2 proxies] - [Application Servers] or maybe [ACE load balancer] - [2 proxies] - [ACE load balancer] - [Application Servers] My idea was that I would setup the load balancers in active-passive mode, to force all messages to use one proxy, and then both the proxies would hit a second load balancer that would be configured in active passive to hit one application server. Whilst the above is not ideal, it does give me resilience, and once the message is in my app servers, I enter a stateless world, and load balance across both nodes of my cluster. However, I am concerned that even a single proxy could send messages out of order, perhaps if 2 messages are recived very close together, message 2 might get processed faster than message 1. Is this possible? Likely? Is there a simple open source proxy (MOD_PROXY?) that can be easily configured to just pass messages through it, and to guarantee to send the messages through in the order they are received. If so which, and finally links to how I should configure it would be great. In fact any links to articles around avoiding "out of order" messages using hardware would be gratefully received. Thanks, ps for those that are interested, the app is a java spring integration application currently on a appliation server.

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