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• How to import .m3u playlist

  - by Charl le Roux

  I exported my my iTunes playlists to .m3u files before I got rid of Win7 completely. Now I would like to import the playlists into Rhythmbox, but can't. My playlists contain windows filenames (e.g. D:\music....) instead of linux filenames (e.g. /mnt/music....). The music is still stored on the exact same disk and folder as it was under windows. I need a script to convert the file names, can anyone help?

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• Why enumerator structs are a really bad idea

  - by Simon Cooper

  If you've ever poked around the .NET class libraries in Reflector, I'm sure you would have noticed that the generic collection classes all have implementations of their IEnumerator as a struct rather than a class. As you will see, this design decision has some rather unfortunate side effects... As is generally known in the .NET world, mutable structs are a Very Bad Idea; and there are several other blogs around explaining this (Eric Lippert's blog post explains the problem quite well). In the BCL, the generic collection enumerators are all mutable structs, as they need to keep track of where they are in the collection. This bit me quite hard when I was coding a wrapper around a LinkedList<int>.Enumerator. It boils down to this code: sealed class EnumeratorWrapper : IEnumerator<int> { private readonly LinkedList<int>.Enumerator m_Enumerator; public EnumeratorWrapper(LinkedList<int> linkedList) { m_Enumerator = linkedList.GetEnumerator(); } public int Current { get { return m_Enumerator.Current; } } object System.Collections.IEnumerator.Current { get { return Current; } } public bool MoveNext() { return m_Enumerator.MoveNext(); } public void Reset() { ((System.Collections.IEnumerator)m_Enumerator).Reset(); } public void Dispose() { m_Enumerator.Dispose(); } } The key line here is the MoveNext method. When I initially coded this, I thought that the call to m_Enumerator.MoveNext() would alter the enumerator state in the m_Enumerator class variable and so the enumeration would proceed in an orderly fashion through the collection. However, when I ran this code it went into an infinite loop - the m_Enumerator.MoveNext() call wasn't actually changing the state in the m_Enumerator variable at all, and my code was looping forever on the first collection element. It was only after disassembling that method that I found out what was going on The MoveNext method above results in the following IL: .method public hidebysig newslot virtual final instance bool MoveNext() cil managed { .maxstack 1 .locals init ( [0] bool CS$1$0000, [1] valuetype [System]System.Collections.Generic.LinkedList`1/Enumerator CS$0$0001) L_0000: nop L_0001: ldarg.0 L_0002: ldfld valuetype [System]System.Collections.Generic.LinkedList`1/Enumerator EnumeratorWrapper::m_Enumerator L_0007: stloc.1 L_0008: ldloca.s CS$0$0001 L_000a: call instance bool [System]System.Collections.Generic.LinkedList`1/Enumerator::MoveNext() L_000f: stloc.0 L_0010: br.s L_0012 L_0012: ldloc.0 L_0013: ret } Here, the important line is 0002 - m_Enumerator is accessed using the ldfld operator, which does the following: Finds the value of a field in the object whose reference is currently on the evaluation stack. So, what the MoveNext method is doing is the following: public bool MoveNext() { LinkedList<int>.Enumerator CS$0$0001 = this.m_Enumerator; bool CS$1$0000 = CS$0$0001.MoveNext(); return CS$1$0000; } The enumerator instance being modified by the call to MoveNext is the one stored in the CS$0$0001 variable on the stack, and not the one in the EnumeratorWrapper class instance. Hence why the state of m_Enumerator wasn't getting updated. Hmm, ok. Well, why is it doing this? If you have a read of Eric Lippert's blog post about this issue, you'll notice he quotes a few sections of the C# spec. In particular, 7.5.4: ...if the field is readonly and the reference occurs outside an instance constructor of the class in which the field is declared, then the result is a value, namely the value of the field I in the object referenced by E. And my m_Enumerator field is readonly! Indeed, if I remove the readonly from the class variable then the problem goes away, and the code works as expected. The IL confirms this: .method public hidebysig newslot virtual final instance bool MoveNext() cil managed { .maxstack 1 .locals init ( [0] bool CS$1$0000) L_0000: nop L_0001: ldarg.0 L_0002: ldflda valuetype [System]System.Collections.Generic.LinkedList`1/Enumerator EnumeratorWrapper::m_Enumerator L_0007: call instance bool [System]System.Collections.Generic.LinkedList`1/Enumerator::MoveNext() L_000c: stloc.0 L_000d: br.s L_000f L_000f: ldloc.0 L_0010: ret } Notice on line 0002, instead of the ldfld we had before, we've got a ldflda, which does this: Finds the address of a field in the object whose reference is currently on the evaluation stack. Instead of loading the value, we're loading the address of the m_Enumerator field. So now the call to MoveNext modifies the enumerator stored in the class rather than on the stack, and everything works as expected. Previously, I had thought enumerator structs were an odd but interesting feature of the BCL that I had used in the past to do linked list slices. However, effects like this only underline how dangerous mutable structs are, and I'm at a loss to explain why the enumerators were implemented as structs in the first place. (interestingly, the SortedList<TKey, TValue> enumerator is a struct but is private, which makes it even more odd - the only way it can be accessed is as a boxed IEnumerator!). I would love to hear people's theories as to why the enumerators are implemented in such a fashion. And bonus points if you can explain why LinkedList<int>.Enumerator.Reset is an explicit implementation but Dispose is implicit... Note to self: never ever ever code a mutable struct.

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• Can WinRT really be used at just the boundaries?

  - by Bret Kuhns

  Microsoft (chiefly, Herb Sutter) recommends when using WinRT with C++/CX to keep WinRT at the boundaries of the application and keep the core of the application written in standard ISO C++. I've been writing an application which I would like to leave portable, so my core functionality was written in standard C++, and I am now attempting to write a Metro-style front end for it using C++/CX. I've had a bit of a problem with this approach, however. For example, if I want to push a vector of user-defined C++ types to a XAML ListView control, I have to wrap my user-defined type in a WinRT ref/value type for it to be stored in a Vector^. With this approach, I'm inevitably left with wrapping a large portion of my C++ classes with WinRT classes. This is the first time I've tried to write a portable native application in C++. Is it really practical to keep WinRT along the boundaries like this? How else could this type of portable core with a platform-specific boundary be handled?

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• Why don't computers store decimal numbers as a second whole number?

  - by SomeKittens

  Computers have trouble storing fractional numbers where the denominator is something other than a solution to 2^x. This is because the first digit after the decimal is worth 1/2, the second 1/4 (or 1/(2^1) and 1/(2^2)) etc. Why deal with all sorts of rounding errors when the computer could have just stored the decimal part of the number as another whole number (which is therefore accurate?) The only thing I can think of is dealing with repeating decimals (in base 10), but there could have been an edge solution to that (like we currently have with infinity).

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• Normals vs Normal maps

  - by KaiserJohaan

  I am using Assimp asset importer (http://assimp.sourceforge.net/lib_html/index.html) to parse 3d models. So far, I've simply pulled out the normal vectors which are defined for each vertex in my meshes. Yet I have also found various tutorials on normal maps... As I understand it for normal maps, the normal vectors are stored in each texel of a normal map, and you pull these out of the normal texture in the shader. Why is there two ways to get the normals, which one is considered best-practice and why?

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• AutoVue Success at Siemens Energy!

  - by prasenjit.niyogi(at)oracle.com

  Siemens Improves Review and Collaboration with Visually Enabled Engineering Platform Siemens Energy Incorporated offers products, solutions, and services for the entire energy conversion chain--from power generation and transmission to distribution. The organization primarily serves energy utilities and industrial companies. Siemens faced challenges in the form of: Long design review cycles and potential field service delays that stemmed from users' inability to digitally access, view, and collaborate on design documents for energy-related projects stored in SAP High costs and IT administration complexity that was caused by multiple design visualization tools Learn how the customized integration of Oracle's AutoVue with SAP, thanks to Oracle partner Lifecycle Technology, significantly streamlined design review processes, improved productivity, and eliminated paper-based collaboration for the field service technicians and engineers. Read the complete snapshot here

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• Speaking in St. Louis on June 14th

  - by Bill Graziano

  I’m going back to speak in St. Louis next month.  I didn’t make it last year and I’m looking forward to it.  You can find additional details on the St. Louis SQL Server user group web site.  The meeting will be held at the Microsoft office and I’ll be speaking at 1PM. I’ll be speaking on the procedure cache.  As people get better and better tuning queries this is the next major piece to understand.  We’ll talk about how and when query plans are reused.  The most common issue I see around odd query plans are stored procedures that use one query plan but the queries run completely different when you extract the SQL and hard code the parameters.  That’s just one of the common issues that I’ll address. There will be a second speaker after I’m done, then a short vendor presentation and a drawing for a netbook.

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• Is SimplePHPBlog a secure blogging engine?

  - by authentictech

  Has anyone used the blog engine SimplePHPBlog? It is a simple blog engine that uses only text files (no database). My problem with it is that the content directory where the texts files are stored appears to require being world writeable/readable (i.e. permission 777) for it to work. This means anyone can access the text files with a browser! These text files include the blog/comment poster's IP and email address! This is not secure or good practice, right?

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• Read only array, deep copy or retrieve copies one by one? (Performance and Memory)

  - by Arthur Wulf White

  In a garbage collection based system, what is the most effective way to handle a read only array if such a structure does not exist natively in the language. Is it better to return a copy of an array or allow other classes to retrieve copies of the objects stored in the array one by one? @JustinSkiles: It is not very broad. It is performance related and can actually be answered specifically for two general cases. You only need very few items: in this situation it's more effective to retrieve copies of the objects one by one. You wish to iterate over 30% or more objects. In this cases it is superior to retrieve all the array at once. This saves on functions calls. Function calls are very expansive when compared to reading directly from an array. A good specific answer could include performance, reading from an array and reading indirectly through a function. It is a simple performance related question.

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• Best practices with Vertices in Open GL

  - by Darestium

  What is the best practice in regards to storing vertex data in Open GL? I.e: struct VertexColored { public: GLfloat position[]; GLfloat normal[]; byte colours[]; } class Terrian { private: GLuint vbo_vertices; GLuint vbo_normals; GLuint vbo_colors; GLuint ibo_elements; VertexColored vertices[]; } or having them stored seperatly in the required class like: class Terrian { private: GLfloat vertices[]; GLfloat normals[]; GLfloat colors[]; GLuint vbo_vertices; GLuint vbo_normals; GLuint vbo_colors; GLuint ibo_elements; }

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• Structure gameobjects and call events

  - by waco001

  I'm working on a 2D tile based game in which the player interacts with other game objects (chests, AI, Doors, Houses etc...). The entire map will be stored in a file which I can read. When loading the tilemap, it will find any tile with the ID that represents a gameobject and store it in a hashmap (right data structure I think?). private static HashMap<Integer, Class<GameObject>> gameObjects = new HashMap<Integer, Class<GameObject>>(); How exactly would I go about calling, and checking for events? I figure that I would just call the update, render and input methods of each gameobject using the hashmap. Should I got towards a Minecraft/Bukkit approach (sorry only example I can think of), where the user registers an event, and it gets called whenever that event happens, and where should I go as in resources to learn about that type of programming, (Java, LWJGL). Or should I just loop through the entire hashmap looking for an event that fits? Thanks waco

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• Manage Your Amazon S3 Account with CloudBerry Explorer

  - by Mysticgeek

  If you have an Amazon S3 account you’re using to backup your data, you might want an easy way to manage it. CloudBerry Explorer is a free app that runs on your desktop an provides an easy way to manage your S3 account. Installation and Setup Just download and install the application with the defaults. When the application launches you’ll be prompted to enter in your username and email to get a registration key. Or you can continue on by clicking Register later. Now you will want to set up your Amazon S3 account. Click on File \ Amazon S3 Accounts. Double-click on the New Account icon.   Next enter in your Amazon account Access and Secret keys, select SSL if you want, then click the Test Connection button. Provided everything was entered correctly, you’ll see the Connection Success screen, just close out of it. Browse and Manage files Once you have your account setup through the Explorer, you can start viewing and managing your files on S3. The left pane shows your S3 buckets and stored files, while the right side shows your local computer. This allows you to manage your files in your Amazon S3 buckets directly from your desktop! It’s very easy to use, and you can drag and drop files from your computer to the S3 account or vice versa. There is also the ability to transfer files between Amazon S3 accounts from within the explorer. Go into Tools and Content Types and you can control the file types by adding, removing, or editing them. If you end up messing something up along the lines, you can always select Reset to defaults and everything will be back to normal. There is a multiple tabbed view so you can easily keep track of your different accounts and local machine. It allows the ability to create new storage buckets directly in the Explorer. Or you can delete buckets as well… Different actions can be accessed from the toolbars or by right-clicking and selecting from the context menu. Here we see a cool option that lets you move your data inside Amazon S3. It is faster and doesn’t cost money by moving the files to your computer first, then to another account. However, if you want data moved to your local machine first, you have that option as well.   Not all features are available in the free version, and if it’s not, you’ll be prompted to purchase a license for the Pro version. We will have a comprehensive review of the Pro version in the near future.    If you ever need help with CloudBerry Explorer, go to Tools \ Diagnostics. It will run a quick diagnostics check and you can send the information to the CloudBerry team for assistance. Delete Files from Amazon S3 To delete a file from you Amazon S3 account, simply highlight the files or folder you want to get rid of then click Delete on the toolbar. You can also right-click the file and select Delete from the Context Menu. Click Yes to the confirmation dialog box… Then you can watch the progress as your files are deleted in the bottom section of the explorer. Conclusion CloudBerry Explorer free version has several neat features that will allow you easy and basic control over you Amazon S3 account. The free version may be enough for basic users, but power users will want to upgrade to the pro version, as it includes a lot more features. Using the free version allows you to get a feel for what CloudBerry Explorer has to offer, and is a good starting point. Keep in mind that Amazon S3 is introducing Reduced Redundancy Storage which will lower the price of data stored. The price drops from $0.15 per GB to only $0.10 per GB. If you’re a Windows Home Server user, check out our review of CloudBerry Online Backup 1.5 for WHS. Download CloudBerry Explorer Free for Amazon S3 Similar Articles Productive Geek Tips CloudBerry Online Backup 1.5 for Windows Home ServerReopen Closed Tabs in Internet ExplorerPreview and Purchase Ebooks with Kindle for PCTroubleshoot and Manage Addons in Internet Explorer 8Beginner Geek: Delete User Accounts in Windows 7 TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server Snagit 10 VMware Workstation 7 Google TV The iPod Revolution Ultimate Boot CD can help when disaster strikes Windows Firewall with Advanced Security – How To Guides Sculptris 1.0, 3D Drawing app AceStock, a Tiny Desktop Quote Monitor

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• How to safely collect bank account from website?

  - by Alexandru Trandafir Catalin

  I want to collect bank account information from my customers on my website. I'd like to do that trough a form, then I will download it to a PC, print it, and then delete it from the website. Or eventually, send it somewhere external right after the user submitted the form so it never gets stored on the website. The goal is to recieve the payment information without having to ask the customer to print, fill manually, and send it over fax. And accomplish this without having to use an external payment gateway. Thank you, Alex.

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• T-SQL User-Defined Functions: the good, the bad, and the ugly (part 1)

  - by Hugo Kornelis

  So you thought that encapsulating code in user-defined functions for easy reuse is a good idea? Think again! SQL Server supports three types of user-defined functions. Only one of them qualifies as good. The other two – well, the title says it all, doesn’t it? The bad: scalar functions A scalar user-defined function (UDF) is very much like a stored procedure, except that it always returns a single value of a predefined data type – and because of that property, it isn’t invoked with an EXECUTE statement,...(read more)

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• Loading Wavefront Data into VAO and Render It

  - by Jordan LaPrise

  I have successfully loaded a triangulated wavefront(.obj) into 6 vectors, the first 3 vectors contain the locations for vertices, uv coords, and normals. The last three have the indices stored for each of the faces. I have been looking into using VAO's and VBO's to render, and I'm not quite sure how to load and render the data. One of my biggest concerns is the fact that indexed rendering only allows you to have one array of indices, meaning I somehow have to make all of the first three vectors the same size, the only way I thought of doing this, is to make 3 new vertex's of equal size, and load in the data for each face, but that would completely defeat the purpose of indexing. Any help would be appreciated. Thanks in advance, Jordan

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• Ubuntu won't start

  - by Tomas

  I've had Ubuntu installed, using WUBI, for some time now - a few months or so. It's worked fine until now, allowing me to login, use it's features etc... Two days ago, I turned on my computer and started Ubuntu. It loaded the GUI fine but just showed the loading screen and even after waiting 10 mins on this screen it still wouldn't show me the login page. I am enthusiastic about web design and development and all of my work, along with my portfolio is stored in Ubuntu. Cheers, Tomas EDIT: I am using 12.04 LTS.

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• Does the Ubuntu One sync work?

  - by bisi

  I have been on this for several hours now, trying to get a simple second folder to sync with my (paid) account. I cannot tell you how many times I removed all devices, removed stored passwords, killed all processes of u1, logged out and back in online...and still, the tick in the file browser (Synchronize this folder) is loading and loading and loading. Also, I have logged out, rebooted countless times. And this is after me somehow managing to get the u1 preferences to finally "connect" again. I have also checked the status of your services, and none are close to what I am experiencing. And I have checked the suggested related questions above! So please, just confirm whether it is a problem on my side, or a problem on your side.

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• How to implement a safe password history

  - by Lorenzo

  Passwords shouldn't be stored in plain text for obvious security reasons: you have to store hashes, and you should also generate the hash carefully to avoid rainbow table attacks. However, usually you have the requirement to store the last n passwords and to enforce minimal complexity and minimal change between the different passwords (to prevent the user from using a sequence like Password_1, Password_2, ..., Password_n). This would be trivial with plain text passwords, but how can you do that by storing only hashes? In other words: how it is possible to implement a safe password history mechanism?

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• Help me classify this type of software architecture

  - by Alex Burtsev

  I read some books about software architecture as we are using it in our project but I can't classify the architecture properly. It's some kind of Enterprise Architecture, but what exactly... SOA, ESB (Enterprise Service Bus), Message Bus, Event Driven SOA, there are so many terms in Enterprise software.... The system is based on custom XML messages exchanges between services. (it's not SOAP, nor any other XML based standard, just plain XML). These messages represent notifications (state changes) that are applied to the Domain model, (it's not like CRUD when you serialize the whole domain object, and pass it to service for persistence). The system is centralized, and system participants use different programming languages and frameworks (c++, c#, java). Also, messages are not processed at the moment they are received as they are stored first and the treatment begins on demand. It's called SOA+EDA -:)

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• Is there something better than a StringBuilder for big blocks of SQL in the code

  - by Eduardo Molteni

  I'm just tired of making a big SQL statement, test it, and then paste the SQL into the code and adding all the sqlstmt.append(" at the beginning and the ") at the end. It's 2011, isn't there a better way the handle a big chunk of strings inside code? Please: don't suggest stored procedures or ORMs. edit Found the answer using XML literals and CData. Thanks to all the people that actually tried to answer the question without questioning me for not using ORM, SPs and using VB edit 2 the question leave me thinking that languages could try to make a better effort for using inline SQL with color syntax, etc. It will be cheaper that developing Linq2SQL. Just something like: dim sql = <sql> SELECT * ... </sql>

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• TFS API Add Favorites programmatically

  - by Tarun Arora

  01 – What are we trying to achieve? In this blog post I’ll be showing you how to add work item queries as favorites, it is also possible to use the same technique to add build definition as favorites. Once a shared query or build definition has been added as favorite it will show up on the team web access.  In this blog post I’ll be showing you a work around in the absence of a proper API how you can add queries to team favorites. 02 – Disclaimer There is no official API for adding favorites programmatically. In the work around below I am using the Identity service to store this data in a property bag which is used during display of favorites on the team web site. This uses an internal data structure that could change over time, there is no guarantee about the key names or content of the values. What is shown below is a workaround for a missing API. 03 – Concept There is no direct API support for favorites, but you could work around it using the identity service in TFS.  Favorites are stored in the property bag associated with the TeamFoundationIdentity (either the ‘team’ identity or the users identity depending on if these are ‘team’ or ‘my’ favorites).  The data is stored as json in the property bag of the identity, the key being prefixed by ‘Microsoft.TeamFoundation.Framework.Server.IdentityFavorites’. References - Microsoft.TeamFoundation.WorkItemTracking.Client - using Microsoft.TeamFoundation.Client; - using Microsoft.TeamFoundation.Framework.Client; - using Microsoft.TeamFoundation.Framework.Common; - using Microsoft.TeamFoundation.ProcessConfiguration.Client; - using Microsoft.TeamFoundation.Server; - using Microsoft.TeamFoundation.WorkItemTracking.Client; Services - IIdentityManagementService2 - TfsTeamService - WorkItemStore 04 – Solution Lets start by connecting to TFS programmatically // Create an instance of the services to be used during the program private static TfsTeamProjectCollection _tfs; private static ProjectInfo _selectedTeamProject; private static WorkItemStore _wis; private static TfsTeamService _tts; private static TeamSettingsConfigurationService _teamConfig; private static IIdentityManagementService2 _ids; // Connect to TFS programmatically public static bool ConnectToTfs() { var isSelected = false; var tfsPp = new TeamProjectPicker(TeamProjectPickerMode.SingleProject, false); tfsPp.ShowDialog(); _tfs = tfsPp.SelectedTeamProjectCollection; if (tfsPp.SelectedProjects.Any()) { _selectedTeamProject = tfsPp.SelectedProjects[0]; isSelected = true; } return isSelected; } Lets get all the work item queries from the selected team project static readonly Dictionary<string, string> QueryAndGuid = new Dictionary<string, string>(); // Get all queries and query guid in the selected team project private static void GetQueryGuidList(IEnumerable<QueryItem> query) { foreach (QueryItem subQuery in query) { if (subQuery.GetType() == typeof(QueryFolder)) GetQueryGuidList((QueryFolder)subQuery); else { QueryAndGuid.Add(subQuery.Name, subQuery.Id.ToString()); } } }   Pass the name of a valid Team in your team project and a name of a valid query in your team project. The team details will be extracted using the team name and query GUID will be extracted using the query name. These details will be used to construct the key and value that will be passed to the SetProperty method in the Identity service.           Key           “Microsoft.TeamFoundation.Framework.Server.IdentityFavorites..<TeamProjectURI>.<TeamId>.WorkItemTracking.Queries.<newGuid1>”           Value           "{"data":"<QueryGuid>","id":"<NewGuid1>","name":"<QueryKey>","type":"Microsoft.TeamFoundation.WorkItemTracking.QueryItem”}"           // Configure a Work Item Query for the given team private static void ConfigureTeamFavorites(string teamName, string queryName) { _ids = _tfs.GetService<IIdentityManagementService2>(); var g = Guid.NewGuid(); var guid = string.Empty; var teamDetail = _tts.QueryTeams(_selectedTeamProject.Uri).FirstOrDefault(t => t.Name == teamName); foreach (var q in QueryAndGuid.Where(q => q.Key == queryName)) { guid = q.Value; } if(guid == string.Empty) { Console.WriteLine("Query '{0}' - Not found!", queryName); return; } var key = string.Format( "Microsoft.TeamFoundation.Framework.Server.IdentityFavorites..{0}.{1}.WorkItemTracking.Queries{2}", new Uri(_selectedTeamProject.Uri).Segments.LastOrDefault(), teamDetail.Identity.TeamFoundationId, g); var value = string.Format( @"{0}""data"":""{1}"",""id"":""{2}"",""name"":""{3}"",""type"":""Microsoft.TeamFoundation.WorkItemTracking.QueryItem""{4}", "{", guid, g, QueryAndGuid.FirstOrDefault(q => q.Value==guid).Key, "}"); teamDetail.Identity.SetProperty(IdentityPropertyScope.Local, key, value); _ids.UpdateExtendedProperties(teamDetail.Identity); Console.WriteLine("{0}Added Query '{1}' as Favorite", Environment.NewLine, queryName); }   If you have any questions or suggestions leave a comment. Enjoy!

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• Computer Networks UNISA - Chap 14 &ndash; Insuring Integrity &amp; Availability

  - by MarkPearl

  After reading this section you should be able to Identify the characteristics of a network that keep data safe from loss or damage Protect an enterprise-wide network from viruses Explain network and system level fault tolerance techniques Discuss issues related to network backup and recovery strategies Describe the components of a useful disaster recovery plan and the options for disaster contingencies What are integrity and availability? Integrity – the soundness of a networks programs, data, services, devices, and connections Availability – How consistently and reliably a file or system can be accessed by authorized personnel A number of phenomena can compromise both integrity and availability including… security breaches natural disasters malicious intruders power flaws human error users etc Although you cannot predict every type of vulnerability, you can take measures to guard against the most damaging events. The following are some guidelines… Allow only network administrators to create or modify NOS and application system users. Monitor the network for unauthorized access or changes Record authorized system changes in a change management system’ Install redundant components Perform regular health checks on the network Check system performance, error logs, and the system log book regularly Keep backups Implement and enforce security and disaster recovery policies These are just some of the basics… Malware Malware refers to any program or piece of code designed to intrude upon or harm a system or its resources. Types of Malware… Boot sector viruses Macro viruses File infector viruses Worms Trojan Horse Network Viruses Bots Malware characteristics Some common characteristics of Malware include… Encryption Stealth Polymorphism Time dependence Malware Protection There are various tools available to protect you from malware called anti-malware software. These monitor your system for indications that a program is performing potential malware operations. A number of techniques are used to detect malware including… Signature Scanning Integrity Checking Monitoring unexpected file changes or virus like behaviours It is important to decide where anti-malware tools will be installed and find a balance between performance and protection. There are several general purpose malware policies that can be implemented to protect your network including… Every compute in an organization should be equipped with malware detection and cleaning software that regularly runs Users should not be allowed to alter or disable the anti-malware software Users should know what to do in case the anti-malware program detects a malware virus Users should be prohibited from installing any unauthorized software on their systems System wide alerts should be issued to network users notifying them if a serious malware virus has been detected. Fault Tolerance Besides guarding against malware, another key factor in maintaining the availability and integrity of data is fault tolerance. Fault tolerance is the ability for a system to continue performing despite an unexpected hardware or software malfunction. Fault tolerance can be realized in varying degrees, the optimal level of fault tolerance for a system depends on how critical its services and files are to productivity. Generally the more fault tolerant the system, the more expensive it is. The following describe some of the areas that need to be considered for fault tolerance. Environment (Temperature and humidity) Power Topology and Connectivity Servers Storage Power Typical power flaws include Surges – a brief increase in voltage due to lightening strikes, solar flares or some idiot at City Power Noise – Fluctuation in voltage levels caused by other devices on the network or electromagnetic interference Brownout – A sag in voltage for just a moment Blackout – A complete power loss The are various alternate power sources to consider including UPS’s and Generators. UPS’s are found in two categories… Standby UPS – provides continuous power when mains goes down (brief period of switching over) Online UPS – is online all the time and the device receives power from the UPS all the time (the UPS is charged continuously) Servers There are various techniques for fault tolerance with servers. Server mirroring is an option where one device or component duplicates the activities of another. It is generally an expensive process. Clustering is a fault tolerance technique that links multiple servers together to appear as a single server. They share processing and storage responsibilities and if one unit in the cluster goes down, another unit can be brought in to replace it. Storage There are various techniques available including the following… RAID Arrays NAS (Storage (Network Attached Storage) SANs (Storage Area Networks) Data Backup A backup is a copy of data or program files created for archiving or safekeeping. Many different options for backups exist with various media including… These vary in cost and speed. Optical Media Tape Backup External Disk Drives Network Backups Backup Strategy After selecting the appropriate tool for performing your servers backup, devise a backup strategy to guide you through performing reliable backups that provide maximum data protection. Questions that should be answered include… What data must be backed up At what time of day or night will the backups occur How will you verify the accuracy of the backups Where and for how long will backup media be stored Who will take responsibility for ensuring that backups occurred How long will you save backups Where will backup and recovery documentation be stored Different backup methods provide varying levels of certainty and corresponding labour cost. There are also different ways to determine which files should be backed up including… Full backup – all data on all servers is copied to storage media Incremental backup – Only data that has changed since the last full or incremental backup is copied to a storage medium Differential backup – Only data that has changed since the last backup is coped to a storage medium Disaster Recovery Disaster recovery is the process of restoring your critical functionality and data after an enterprise wide outage has occurred. A disaster recovery plan is for extreme scenarios (i.e. fire, line fault, etc). A cold site is a place were the computers, devices, and connectivity necessary to rebuild a network exist but they are not appropriately configured. A warm site is a place where the computers, devices, and connectivity necessary to rebuild a network exists with some appropriately configured devices. A hot site is a place where the computers, devices, and connectivity necessary to rebuild a network exists and all are appropriately configured.

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• PIN request at each login after update to Maverick

  - by Giacomo Verticale

  I have a netbook with included 3G mobile broadband card (Huawei E620). I have configured the broadband network connection in the Network Manager and it works perfectly. However since Maverick upgrade, a window appears just after login I asking for the SIMcard PIN. This happens every time I log in and did not happen with Lucid. Note that the PIN is stored in the configuration of the mobile broadband connection and Lucid was satisfied with that. Is there a way to prevent this request or, at least, to have the system rember the PIN and stop ansking for it? If it may be useful, the broadband network connection is configured as not being available for other users. Also, I would like to keep the SIMcard asking for the PIN; only I do not want to insert it manually at login.

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• Using Transaction Logging to Recover Post-Archived Essbase data

  - by Keith Rosenthal

  Data recovery is typically performed by restoring data from an archive.  Data added or removed since the last archive took place can also be recovered by enabling transaction logging in Essbase.  Transaction logging works by writing transactions to a log store.  The information in the log store can then be recovered by replaying the log store entries in sequence since the last archive took place.  The following information is recorded within a transaction log entry: Sequence ID Username Start Time End Time Request Type A request type can be one of the following categories: Calculations, including the default calculation as well as both server and client side calculations Data loads, including data imports as well as data loaded using a load rule Data clears as well as outline resets Locking and sending data from SmartView and the Spreadsheet Add-In.  Changes from Planning web forms are also tracked since a lock and send operation occurs during this process. You can use the Display Transactions command in the EAS console or the query database MAXL command to view the transaction log entries. Enabling Transaction Logging Transaction logging can be enabled at the Essbase server, application or database level by adding the TRANSACTIONLOGLOCATION essbase.cfg setting.  The following is the TRANSACTIONLOGLOCATION syntax: TRANSACTIONLOGLOCATION [appname [dbname]] LOGLOCATION NATIVE ENABLE | DISABLE Note that you can have multiple TRANSACTIONLOGLOCATION entries in the essbase.cfg file.  For example: TRANSACTIONLOGLOCATION Hyperion/trlog NATIVE ENABLE TRANSACTIONLOGLOCATION Sample Hyperion/trlog NATIVE DISABLE The first statement will enable transaction logging for all Essbase applications, and the second statement will disable transaction logging for the Sample application.  As a result, transaction logging will be enabled for all applications except the Sample application. A location on a physical disk other than the disk where ARBORPATH or the disk files reside is recommended to optimize overall Essbase performance. Configuring Transaction Log Replay Although transaction log entries are stored based on the LOGLOCATION parameter of the TRANSACTIONLOGLOCATION essbase.cfg setting, copies of data load and rules files are stored in the ARBORPATH/app/appname/dbname/Replay directory to optimize the performance of replaying logged transactions.  The default is to archive client data loads, but this configuration setting can be used to archive server data loads (including SQL server data loads) or both client and server data loads. To change the type of data to be archived, add the TRANSACTIONLOGDATALOADARCHIVE configuration setting to the essbase.cfg file.  Note that you can have multiple TRANSACTIONLOGDATALOADARCHIVE entries in the essbase.cfg file to adjust settings for individual applications and databases. Replaying the Transaction Log and Transaction Log Security Considerations To replay the transactions, use either the Replay Transactions command in the EAS console or the alter database MAXL command using the replay transactions grammar.  Transactions can be replayed either after a specified log time or using a range of transaction sequence IDs. The default when replaying transactions is to use the security settings of the user who originally performed the transaction.  However, if that user no longer exists or that user's username was changed, the replay operation will fail. Instead of using the default security setting, add the REPLAYSECURITYOPTION essbase.cfg setting to use the security settings of the administrator who performs the replay operation.  REPLAYSECURITYOPTION 2 will explicitly use the security settings of the administrator performing the replay operation.  REPLAYSECURITYOPTION 3 will use the administrator security settings if the original user’s security settings cannot be used. Removing Transaction Logs and Archived Replay Data Load and Rules Files Transaction logs and archived replay data load and rules files are not automatically removed and are only removed manually.  Since these files can consume a considerable amount of space, the files should be removed on a periodic basis. The transaction logs should be removed one database at a time instead of all databases simultaneously.  The data load and rules files associated with the replayed transactions should be removed in chronological order from earliest to latest.  In addition, do not remove any data load and rules files with a timestamp later than the timestamp of the most recent archive file. Partitioned Database Considerations For partitioned databases, partition commands such as synchronization commands cannot be replayed.  When recovering data, the partition changes must be replayed manually and logged transactions must be replayed in the correct chronological order. If the partitioned database includes any @XREF commands in the calc script, the logged transactions must be selectively replayed in the correct chronological order between the source and target databases. References For additional information, please see the Oracle EPM System Backup and Recovery Guide.  For EPM 11.1.2.2, the link is http://docs.oracle.com/cd/E17236_01/epm.1112/epm_backup_recovery_1112200.pdf

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• How to apply a changelog file to packages in a PPA when building from recipe?

  - by rafalcieslak

  When my package gets build by launchpad using a recipe, it ignores the ./debian/changelog file I provide, and it generates a useless one, like following: harmonyseq (0.14~natty1) maverick; urgency=low * Auto build. -- Rafal Cieslak <[email protected]> Tue, 25 Jan 2011 16:56:57 +0000 It would be much better if launchpad stored the list of changes I prepared in the changelog file, rather than just putting there "Auto build". How do I force launchpad to use the list of changes from my changelog file, when building packages from a recipe?

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