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  • 4 Key Ingredients for the Cloud

    - by Kellsey Ruppel
    It's a short week here with the US Thanksgiving Holiday. So, before we put on our stretch pants and get ready to belly up to the dinner table for turkey, stuffing and mashed potatoes, let's spend a little time this week talking about the Cloud (kind of like the feathery whipped goodness that tops the infamous Thanksgiving pumpkin pie!) But before we dive into the Cloud, let's do a side by side comparison of the key ingredients for each. Cloud Whipped Cream  Application Integration  1 cup heavy cream  Security  1/4 cup sugar  Virtual I/O  1 teaspoon vanilla  Storage  Chilled Bowl It’s no secret that millions of people are connected to the Internet. And it also probably doesn’t come as a surprise that a lot of those people are connected on social networking sites.  Social networks have become an excellent platform for sharing and communication that reflects real world relationships and they play a major part in the everyday lives of many people. Facebook, Twitter, Pinterest, LinkedIn, Google+ and hundreds of others have transformed the way we interact and communicate with one another.Social networks are becoming more than just an online gathering of friends. They are becoming a destination for ideation, e-commerce, and marketing. But it doesn’t just stop there. Some organizations are utilizing social networks internally, integrated with their business applications and processes and the possibility of social media and cloud integration is compelling. Forrester alone estimates enterprise cloud computing to grow to over $240 billion by 2020. It’s hard to find any current IT project today that is NOT considering cloud-based deployments. Security and quality of service concerns are no longer at the forefront; rather, it’s about focusing on the right mix of capabilities for the business. Cloud vs. On-Premise? Policies & governance models? Social in the cloud? Cloud’s increasing sophistication, security in applications, mobility, transaction processing and social capabilities make it an attractive way to manage information. And Oracle offers all of this through the Oracle Cloud and Oracle Social Network. Oracle Social Network is a secure private network that provides a broad range of social tools designed to capture and preserve information flowing between people, enterprise applications, and business processes. By connecting you with your most critical applications, Oracle Social Network provides contextual, real-time communication within and across enterprises. With Oracle Social Network, you and your teams have the tools you need to collaborate quickly and efficiently, while leveraging the organization’s collective expertise to make informed decisions and drive business forward. Oracle Social Network is available as part of a portfolio of application and platform services within the Oracle Cloud. Oracle Cloud offers self-service business applications delivered on an integrated development and deployment platform with tools to rapidly extend and create new services. Oracle Social Network is pre-integrated with the Fusion CRM Cloud Service and the Fusion HCM Cloud Service within the Oracle Cloud. If you are looking for something to watch as you veg on the couch in a post-turkey dinner hangover, you might consider watching these how-to videos! And yes, it is perfectly ok to have that 2nd piece of pie

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  • Bowing to User Experience

    As a consumer of geeky news it is hard to check my Google Reader without running into two or three posts about Apples iPad and in particular the changes to the developer guidelines which seemingly restrict developers to using Apples Xcode tool and Objective-C language for iPad apps. One of the alternatives to Objective-C affected, is MonoTouch, an option with some appeal to me as it is based on the Mono implementation of C#. Seemingly restricted is the key word here, as far as I can tell, no official announcement has been made about its fate. For more details around MonoTouch for iPhone OS, check out Miguel de Icazas post: http://tirania.org/blog/archive/2010/Apr-28.html. These restrictions have provoked some outrage as the perception is that Apple is arrogantly restricting developers freedom to create applications as they choose and perhaps unwittingly shortchanging iPhone/iPad users who wont benefit from these now never-to-be-made great applications. Apples response has mostly been to say they are concentrating on providing a certain user experience to their customers, and to do this, they insist everyone uses the tools they approve. Which isnt a surprising line of reasoning given Apple restricts the hardware used and content of the apps already. The vogue term for this approach is curated, as in a benevolent museum director selecting only the finest artifacts for display or a wise gardener arranging the plants in a garden just so. If this is what a curated experience is like it is hard to argue that consumers are not responding. My iPhone is probably the most satisfying piece of technology I own. Coming from the Razr, it really was an revolution in how the form factor, interface and user experience all tied together. While the curated approach reinvented the smart phone genre, it is easy to forget that this is not a new approach for Apple. Macbooks and Macs are Apple hardware that run Apple software. And theyve been successful, but not quite in the same way as the iPhone or iPad (based on early indications). Why not? Well a curated approach can only be wildly successful if the curator a) makes the right choices and b) offers choices that no one else has. Although its advantages are eroding, the iPhone was different from other phones, a unique, focused, touch-centric experience. The iPad is an attempt to define another category of computing. Macs and Macbooks are great devices, but are not fundamentally a different user experience than a PC, you still have windows, file folders, mouse and keyboard, and similar applications. So the big question for Apple is can they hold on to their market advantage, continuing innovating in user experience and stay on top? Or are they going be like Xerox, and the rest of the world says thank you for the windows metaphor, now let me implement that better? It will be exciting to watch, with Android already a viable competitor and Microsoft readying Windows Phone 7. And to close the loop back to the restrictions on developing for iPhone OS. At this point the main target appears to be Adobe and Adobe Flash. Apples calculation is that a) they dont need those developers or b) the developers they want will learn Apples stuff anyway. My guess is that they are correct; that as much as I like the idea of developers having more options, I am not going to buy a competitors product to spite Apple unless that product is just as usable. For a non-technical consumer, I dont know that this conversation even factors into the buying decision. If it did, wed be talking about how Microsoft is trying to retake a slice of market share from the behemoth that is Linux.Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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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. EDIT: In the mean time, here is what has changed, on top of what is mentioned just above. • My files went from 0MB to 71.9MB, and is still rising. • My first folder of 400.2MB is being filled with the data as I write this. The second folder has the folder sub-structure in place. • Both folders now show in the File Browser that it will be synchronized. I believe that right now, it is all back to normal and working fine, and I guess that's what a good night's sleep can do ;). And we're now only back to the point where synchronizing is slow, but will pick up with the release of Natty (https://wiki.ubuntu.com/UbuntuOne/FAQ/WhyIsItTakingSoLongForMyFilesToSync). But to get to the questions: My about says I use 11.04, Natty Narwhal, but I am quite sure the last distribution I installed was 10.10. Folder A is 400.2MB, and Folder B is 29.5MB I am on a DSL line, behind a regular fritz.box setting. No proxy servers in use, and I did not install any particular firewall features. No physical firewall, just the router (on which I have a TV signal as well), and 2 switches to get to this floor. Status: inactive The ubuntuone-indicator runs the same window as when I click on my name on the top-right corner and select Ubuntu one, or in the Control Center choose Ubuntu one. It wasn't supposed to go further than this was it?

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  • The long road to bug-free software

    - by Tony Davis
    The past decade has seen a burgeoning interest in functional programming languages such as Haskell or, in the Microsoft world, F#. Though still on the periphery of mainstream programming, functional programming concepts are gradually seeping into the imperative C# language (for example, Lambda expressions have their root in functional programming). One of the more interesting concepts from functional programming languages is the use of formal methods, the lofty ideal behind which is bug-free software. The idea is that we write a specification that describes exactly how our function (say) should behave. We then prove that our function conforms to it, and in doing so have proved beyond any doubt that it is free from bugs. All programmers already use one form of specification, specifically their programming language's type system. If a value has a specific type then, in a type-safe language, the compiler guarantees that value cannot be an instance of a different type. Many extensions to existing type systems, such as generics in Java and .NET, extend the range of programs that can be type-checked. Unfortunately, type systems can only prevent some bugs. To take a classic problem of retrieving an index value from an array, since the type system doesn't specify the length of the array, the compiler has no way of knowing that a request for the "value of index 4" from an array of only two elements is "unsafe". We restore safety via exception handling, but the ideal type system will prevent us from doing anything that is unsafe in the first place and this is where we start to borrow ideas from a language such as Haskell, with its concept of "dependent types". If the type of an array includes its length, we can ensure that any index accesses into the array are valid. The problem is that we now need to carry around the length of arrays and the values of indices throughout our code so that it can be type-checked. In general, writing the specification to prove a positive property, even for a problem very amenable to specification, such as a simple sorting algorithm, turns out to be very hard and the specification will be different for every program. Extend this to writing a specification for, say, Microsoft Word and we can see that the specification would end up being no simpler, and therefore no less buggy, than the implementation. Fortunately, it is easier to write a specification that proves that a program doesn't have certain, specific and undesirable properties, such as infinite loops or accesses to the wrong bit of memory. If we can write the specifications to prove that a program is immune to such problems, we could reuse them in many places. The problem is the lack of specification "provers" that can do this without a lot of manual intervention (i.e. hints from the programmer). All this might feel a very long way off, but computing power and our understanding of the theory of "provers" advances quickly, and Microsoft is doing some of it already. Via their Terminator research project they have started to prove that their device drivers will always terminate, and in so doing have suddenly eliminated a vast range of possible bugs. This is a huge step forward from saying, "we've tested it lots and it seems fine". What do you think? What might be good targets for specification and verification? SQL could be one: the cost of a bug in SQL Server is quite high given how many important systems rely on it, so there's a good incentive to eliminate bugs, even at high initial cost. [Many thanks to Mike Williamson for guidance and useful conversations during the writing of this piece] Cheers, Tony.

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  • Setting MTU on Exalogic

    - by csoto
    For many reasons, a system administrator may want to change the MTU settings of a server. But in a system like Exalogic which contains lots of interconnected nodes and other various components, it's important to understand how this applies to the different networks. For example, when bringing up bonding of InfiniBand an error like the following may be thrown: Bringing up interface bond1: SIOCSIFMTU: Invalid argument Both scripts ifcfg-ib0 and ifcfg-ib1 (from the /etc/sysconfig/network-scripts/ direectory) have MTU set to 65500, which is a valid MTU value only if all IPoIB slaves operate in connected mode and are configured with the same value, so the line below must be added to both network scripts and then restart the network: CONNECTED_MODE=yes By the way, an error of the form “SIOCSIFMTU: Invalid argument” indicates that the requested MTU was rejected by the kernel. Typically this would be due to it exceeding the maximum value supported by the interface hardware. In that case you must either reduce the MTU to a value that is supported or obtain more capable hardware. This problem has been seen when trying to modify the MTU using the ifconfig command, like the output of the example below: [root@elxxcnxx ~]# ifconfig ib1 mtu 65520 SIOCSIFMTU: Invalid argument It's important to insist that in most cases the nodes must be rebooted after the MTU size has been changed. Although in some circumstances it may work without a reboot, it is not how it is typically documented. Now, in order to achieve a reduced memory consumption and improve performance for network traffic received on IPoIB related interfaces, it is recommend to reduce the MTU value in interface configuration files for IPoIB related bonds from 65520 to 64000. The change needs to be made to interface configuration files under the /etc/sysconfig/network-scripts directory and applies to the interface configuration files for bonds over IPoIB related slave devices, for example /etc/sysconfig/network-scripts/ifcfg-bond1. However, keep in mind that the numeric portion of the interface filenames that corresponding to IPoIB interfaces is expected to vary across compute nodes and vServers and so cannot be relied upon to identify which interface files are for bonds are over IPoIB rather than EoIB related slave interfaces. To fix these MTU values to the recommended settings, there are very useful instructions and a script on the MOS Note 1624434.1, and it's applicable physical and virtual configurations of Exalogic. Regarding the recommended MTU value for EoIB related interfaces, its maximum appropriate value is 1500. If for some reason a vServer has been created with a higher value (set on the /etc/sysconfig/network-scripts/ifcfg-bond0 file), then it must be fixed. An error like the following could be thrown under this circumstance: [root@vServer ~]# service network restart ... Bringing up interface bond0:  SIOCSIFMTU: Invalid argument Also an error like the one below can be seen on the /var/log/messages file of the vServer: kernel: T5074835532 [mlx4_vnic] eth1:vnic_change_mtu:360: failed: new_mtu 64000 2026 The MOS Note 1611657.1 is very useful for this purpose.

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  • Oracle Linux Hands-on Lab from your Home? Yes You Can Do That!

    - by Zeynep Koch
    We're taking the very popular OTN Sysadmin Days and going virtual! We have two days to choose from: Americas - Tuesday January 15th, 2013 9:00 a.m – 1:00 p.m. PT / 12:00 p.m. – 4:00 p.m. ET / 1:00 p.m. - 5:00 p.m. BRT EMEA -  Tuesday January 29th, 2013 - 9:00 a.m – 13:00 p.m GMT / 10:00 a.m – 14:00 p,m CET / 12:00 p.m – 16:00 p.m AST / 13:00 p.m – 17:00 p,m MSK / 14:30 p.m – 18:30 p.m IST You'll be able to perform real-world tasks with Oracle Linux and if you have questions you can ask for help from the Oracle experts through chat window. There's one caveat: you'll have to do a little homework ahead of time. Load the virtual images onto your laptop, find the instructions, and make sure everything is working properly. This wiki https://wikis.oracle.com/display/virtualsysadminday/Home explains what you need to do. If you have questions, ask them as comments to the wiki:https://wikis.oracle.com/display/virtualsysadminday/Home.  Oracle Linux Track  1. Oracle Linux Technology Overview - In this session we will go over the latest Oracle Linux features including tools for Linux administration such as the Unbreakable Linux Network (ULN) and public yum. We will also show you a demo of Ksplice zero downtime kernel updates, only available to Oracle Linux customers. You will see how easy it is to switch from Red Hat support to Oracle Linux support by using ULN. Last but not least, we’ll introduce the 3 hands-on labs that will follow this session in the Linux track. 2. HOL: Package Management -  In this lab session you will use the package management on Oracle Linux using RPM and yum. Some of the tasks that you will experience include listing installed packages, obtaining additional information about packages, searching for packages and installing/updating them as well as verifying package integrity and removing software. We’ll also review Linux services and run levels, how to start and stop them, checking the status of a particular service and enabling a service to be started automatically at system boot. 3. HOL: Storage Management - In this hands-on lab session, you will learn about storage management with LVM2, the Linux Logical Volume Manager, preparing block devices, creating physical and logical volumes, creating file systems on top of logical volumes, and resizing file systems dynamically. You will also practice setting up software RAID devices, configuring encrypted block devices.Btrfs File System - In this hands-on lab session, we will introduce you to Btrfs file system. You will be able to create and mount a Btrfs file system and learn to setup a mirrored/striped file system across multiple block devices. You’ll also learn how to add and remove block devices, and create file system snapshots. Register for this FREE event.

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  • Defining a service layer: the text-based adventure

    - by Stacy Vicknair
    Applications these days have more options than ever for a user interface, and it’s only going to grow. A successful product might require native applications for mobile devices, a regular web implementation, or even a gaming console. These systems often will be centralized and data driven. The solution is one that’s fairly solitary, a service layer! Simply put, take what’s shared and put it behind a physical or abstract layer that defines the boundary between the specific user interface and the shared content.   I know, I know, none of this is complicated. But some times it can be difficult to discern what belongs on which side of the line. For instance, say we’re creating a service that will provide content for both an ASP.NET MVC application and a WP7 application. Although the content served to each application is the same, there are different paradigms and patterns for displaying that data in the different environments. In ASP.NET MVC, you may create a model specific to a page that combines necessary information. In the WP7 application you might require different sets of data that you will connect via MVVM with the view. The general rule of thumb is that any shared content, business rules, or data should exist separately. Any element that is specific to the current UI implementation should be included in a separate library or with the UI implementation itself. The WP7 application doesn’t need my MVC specific model classes. My MVC application doesn’t require those INotifyPropertyChanged viewmodels that the WP7 application depends on. In both cases, there should be additional processing done above the service layer to massage the data to the application’s specific needs.   Service-ocalypse: the text based adventure What helps me the most about deciding whether or not something belongs coupled to the UI implementation or in the shared implementation is thinking of the simplest implementation you could have: a console application. You might have played a game like Peasant’s Quest: The console app is the text based adventure game version of your application. If you’re service was consumed in its simplest form, you would simply have a console based API for it that issues requests. Maybe those requests aren’t SWIM TO BOAT, but they might be CREATE USER JOHN. If I issue a request, I expect that request to be issued to the service. If the service has any exceptions or issues with my input, that business logic should be encapsulated in that service, not implemented in the UI. The service layer should be your functional application in its entirety, and anything above that layer should only assist with the display of that information.

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  • Why can't the IT industry deliver large, faultless projects quickly as in other industries?

    - by MainMa
    After watching National Geographic's MegaStructures series, I was surprised how fast large projects are completed. Once the preliminary work (design, specifications, etc.) is done on paper, the realization itself of huge projects take just a few years or sometimes a few months. For example, Airbus A380 "formally launched on Dec. 19, 2000", and "in the Early March, 2005", the aircraft was already tested. The same goes for huge oil tankers, skyscrapers, etc. Comparing this to the delays in software industry, I can't help wondering why most IT projects are so slow, or more precisely, why they cannot be as fast and faultless, at the same scale, given enough people? Projects such as the Airbus A380 present both: Major unforeseen risks: while this is not the first aircraft built, it still pushes the limits if the technology and things which worked well for smaller airliners may not work for the larger one due to physical constraints; in the same way, new technologies are used which were not used yet, because for example they were not available in 1969 when Boeing 747 was done. Risks related to human resources and management in general: people quitting in the middle of the project, inability to reach a person because she's on vacation, ordinary human errors, etc. With those risks, people still achieve projects like those large airliners in a very short period of time, and despite the delivery delays, those projects are still hugely successful and of a high quality. When it comes to software development, the projects are hardly as large and complicated as an airliner (both technically and in terms of management), and have slightly less unforeseen risks from the real world. Still, most IT projects are slow and late, and adding more developers to the project is not a solution (going from a team of ten developer to two thousand will sometimes allow to deliver the project faster, sometimes not, and sometimes will only harm the project and increase the risk of not finishing it at all). Those which are still delivered may often contain a lot of bugs, requiring consecutive service packs and regular updates (imagine "installing updates" on every Airbus A380 twice per week to patch the bugs in the original product and prevent the aircraft from crashing). How can such differences be explained? Is it due exclusively to the fact that software development industry is too young to be able to manage thousands of people on a single project in order to deliver large scale, nearly faultless products very fast?

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  • Oracle Executive Strategy Brief: Enterprise-Grade Cloud Applications

    - by B Shashikumar
    Cloud Computing has clearly evolved into one of the dominant secular trends in the industry. Organizations are looking to the cloud to change how they buy and consume IT. And its no longer about just lower up-front costs. The cloud promises to deliver greater agility and free up resources to focus on innovation versus running and maintaining systems. But are organizations actually realizing these benefits? The full promise of cloud is not being realized by customers who entrust their business to multiple niche cloud providers. While almost 9 out of 10 companies  expect more IT agility with cloud, only 47% are actually getting it (Source: 2011 State of Cloud Survey by Symantec). These niche cloud customers have also seen the promises of lower costs, efficiency gains, improved security, and compliance go unfulfilled. Having one cloud provider for customer relationship management (CRM) and another for human capital management (HCM), and then trying to glue these proprietary systems together while integrating to a back-office financial system can add to complexity and long-term costs. Completing a business process or generating an integrated report is cumbersome, and leverages incomplete data. Why can’t niche cloud providers deliver on the full promise of cloud? It’s simple: you still need to complete business processes. You still need reporting that enables you to take action using data from multiple systems. You still have to comply with SOX and other industry regulations. These requirements don’t go away just because you deploy in the cloud. Delivering lower up-front costs by enabling customers to buy software as a service (SaaS) is the easy part. To get real value that lasts longer than your quarterly report, it’s important to realize the benefits of cloud without compromising on functionality and while having the right level of control and flexibility. This is the true promise of cloud. Oracle’s cloud strategy centers around delivering the benefits of cloud—without compromise. We uniquely empower our customers with complete solutions and choice. From the richest functionality to integrated reporting and great user experience. It’s all available in the cloud. And it works not just with other Oracle cloud applications, but with your existing Oracle and third-party systems as well. This helps protect your current investments and extend their value as you journey to the cloud. We’ve made the necessary investments not only in our applications but also in the underlying technology that makes it all run—from the platform down to the hardware and operating system. We make it all. And we’ve engineered it to work together and be highly optimized for our customers, in the cloud. With Oracle enterprise-grade cloud applications, you get the benefits of cloud plus more power, more choice, and more confidence. Read more about how you can realize the true advantage of Cloud with Oracle Enterprise-grade Cloud applications in the Oracle Executive Strategy Brief here.  You can also attend an Oracle Cloud Conference event at a city near you. Register here. 

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  • Data Source Use of Oracle Edition Based Redefinition (EBR)

    - by Steve Felts
    Edition-based redefinition is a new feature in the 11gR2 release of the Oracle database. It enables you to upgrade the database component of an application while it is in use, thereby minimizing or eliminating down time. It works by allowing for a pre-upgrade and post-upgrade view of the data to exist at the same time, providing a hot upgrade capability. You can then specify which view you want for a particular session.  See the Oracle Database Advanced Application Developer's Guide for further information. There is also a good white paper at Edition Based Definition. Using this feature of the Oracle database does not require any new WebLogic Server functionality. It is set for each connection in the pool automatically by simply specifying SQL ALTER SESSION SET EDITION = edition_name in the Init SQL parameter in the data source configuration. This can be configured either via the console or via WLST (setInitSQL on the JDBCConnectionPoolParams). This SQL statement is executed for each newly created physical database connection.Note that we are assuming that a data source references only one edition of the database. To make use of this feature, you would have an earlier version of the application with a data source that references the earlier EDITION and a later version of the application with a data source that references the later EDITION.   Once you start talking about multiple versions of a WLS application, you should be using the WLS "side-by-side" or "versioned" deployment feature.  See Developing Applications for Production Redeployment for more information.  By combining Oracle database EBR and WLS versioned deployment, the application can be failed over with no downtime, making the combination of features more powerful than either independently. There is a catch - you need to be running with a versioned database and a versioned application initially so then you can switch versions.  The recommended way to version a WLS application is to simply add the "Weblogic-Application-Version" property in the MANIFEST.MF file(you can also specify it at deployment time). The recommended way to configure the data source is to use a packaged data source descriptor that's stored in the ear or war so that everything is self-contained.  There are some restrictions.  You can't use a packaged data source with Logging Last Resource (LLR) - you need to use a system resource.  You can't use an application-scoped packaged data source with EmulateTwoPhaseCommit for the global-transactions-protocol with a versioned application - use a global scope.  See Configuring JDBC Application Modules for Deployment for more details. There's one known problem - it doesn't work correctly with an XA data source (patch available with bug 14075837).

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  • TechEd 2010 Day Three: The Database Designer (Isn't)

    - by BuckWoody
    Yesterday at TechEd 2010 here in New Orleans I worked the front-booth, answering general SQL Server questions for the masses. I was actually a little surprised to find most of the questions I got were from folks that wanted to know more about Stream Insight and Master Data Services. In past conferences I've been asked a lot of "free consulting" questions, about problems folks have had from older products. I don't mind that a bit - in fact, I'm always happy to help in any way I can. But this time people are really interested in the new features in the product, and I like that they are thinking ahead, not just having to solve problems in production. My presentation was on "Database Design in an Hour". We had the usual fun, and SideShow Bob made an appearance - I kid you not. The guy in the back of the room looked just like Sideshow Bob, so I quickly held a "bes thair" contest, and he won. Duing the presentation, I explain the tools you can use to design databases. I also explain that the "Database Designer" tool in SQL Server Management Studio (SSMS) isn't truly a desinger - it uses non-standard notation, doesn't have a meta-data dictionary, and worst of all, it works at the physical level. In other words, whatever you do in SSMS will automatically change the field/table/relationship structures in the database. We fixed this in SSMS 2008 and higher by adding an option to block that, but the tool is not a good design function nonetheless. To be fair, no one I know of at Microsoft recommends that it is - but I was shocked to hear so many developers in the room defending it as a good tool. I think the main issue for someone who doesn't have to work with Relational Systems a great deal is that it can be difficult to figure out Foreign Keys. The syntax makes them look "backwards", so it's just easier to grab a field and place it on the table you want to point to. There are options. You can download a couple of free tools (CA has a community edition of ER-WIN, Quest has one, and Embarcadero also has one) and if you design more than one or two databases a year, it may be worth buying a true design tool. For years I used Visio, but we changed it so that it doesn't forward-engineer (create the DDL) any more, so it isn't a true design tool either. So investigate those free and not-so-free tools. You'll find they help you in your job - but stay away from the Database Designer in SSMS. Or I'll send Sideshow Bob over there to straighten you out. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • Why can't Ubuntu find an ext3 filesystem on my hard-drive?

    - by urig
    This question is related to this question: Not enough components to start the RAID array? I'm trying to retrieve data from a "Western Digital MyBook World Edition (white light)" NAS device. This is basically an embedded Linux box with a 1TB HDD in it formatted in ext3. It stopped booting one day for no apparent reason. I have extracted the HDD from the NAS device and installed it in a desktop machine running Ubuntu 10.10 in the hope of accessing the files on the drive. I have followed instructions in this forum post, intended to mount the drive through Terminal: http://mybookworld.wikidot.com/forum/t-90514/how-to-recover-data-from-wd-my-book-world-edition-nas-device#post-976452 I have identified the partition that I want to mount and recover files from as /dev/sd4 by running "fdisk -l" and getting this: Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes 255 heads, 63 sectors/track, 121601 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x0001cf00 Device Boot Start End Blocks Id System /dev/sdb1 5 248 1959930 fd Linux raid autodetect /dev/sdb2 249 280 257040 fd Linux raid autodetect /dev/sdb3 281 403 987997+ fd Linux raid autodetect /dev/sdb4 404 121601 973522935 fd Linux raid autodetect// When I try to mount using: "mount -t ext3 /dev/sdb4 /media/xyz" I get the following error: mount: wrong fs type, bad option, bad superblock on /dev/sdb4, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so And "dmesg | tail" shows me: [ 15.184757] [drm] Initialized nouveau 0.0.16 20090420 for 0000:01:00.0 on minor 0 [ 15.986859] [drm] nouveau 0000:01:00.0: Allocating FIFO number 1 [ 15.988379] [drm] nouveau 0000:01:00.0: nouveau_channel_alloc: initialised FIFO 1 [ 16.353379] EXT4-fs (sda5): re-mounted. Opts: errors=remount-ro,commit=0 [ 16.705944] tg3 0000:02:00.0: eth0: Link is up at 100 Mbps, full duplex [ 16.705951] tg3 0000:02:00.0: eth0: Flow control is off for TX and off for RX [ 16.706102] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready [ 19.125673] EXT4-fs (sda5): re-mounted. Opts: errors=remount-ro,commit=0 [ 27.600012] eth0: no IPv6 routers present [ 373.478031] EXT3-fs (sdb4): error: can't find ext3 filesystem on dev sdb4. I guess that last line is the punch line :) Why can't it find the ext3 filesystem on my drive? What do I need to do to mount this partition and copy its contents? Does it have anything to do with the drive being part of a RAID Array (see question mentioned above)? Many thanks to any who can help.

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  • Toshiba wireless is blocked

    - by zorrillo
    I have the same problem, a 32 bits toshiba nb255, it first had the windows 7 bu next I installed the ubuntu 11.04. The wifi does not turn on. I used the following issues the commands rfkill unblock wlan0, sudo ifconfig wlan0 down; they were not able. by setting up the bios in advanced menu, the wireless communication sw in ON, but it did not work also. neither the utilities toshiba nor utilities of ubuntu (wicd, wifi radar). by using gedit to file group, nothing. by installing madwifi packet, nothing. by exporting the wifi driver from windows to ubuntu, by means of the NDISwrapper packet, neither. I put the current scripts of the ouput of the cli root@zorrillo:~# rfkill list 0: phy0: Wireless LAN Soft blocked: no Hard blocked: yes root@zorrillo:~# sudo lspci | grep Atheros 07:00.0 Network controller: Atheros Communications Inc. AR9285 Wireless Network Adapter (PCI-Express) (rev 01) root@zorrillo:~# root@zorrillo:~# ifconfig -a eth0 Link encap:Ethernet direcciónHW 88:ae:1d:47:df:e1 ACTIVO DIFUSIÓN MULTICAST MTU:1500 Métrica:1 Paquetes RX:0 errores:0 perdidos:0 overruns:0 frame:0 Paquetes TX:0 errores:0 perdidos:0 overruns:0 carrier:0 colisiones:0 long.colaTX:1000 Bytes RX:0 (0.0 B) TX bytes:0 (0.0 B) Interrupción:43 Dirección base: 0xe000 lo Link encap:Bucle local Direc. inet:127.0.0.1 Másc:255.0.0.0 Dirección inet6: ::1/128 Alcance:Anfitrión ACTIVO BUCLE FUNCIONANDO MTU:16436 Métrica:1 Paquetes RX:8 errores:0 perdidos:0 overruns:0 frame:0 Paquetes TX:8 errores:0 perdidos:0 overruns:0 carrier:0 colisiones:0 long.colaTX:0 Bytes RX:480 (480.0 B) TX bytes:480 (480.0 B) ppp0 Link encap:Protocolo punto a punto Direc. inet:189.203.115.236 P-t-P:192.168.226.1 Másc:255.255.255.255 ACTIVO PUNTO A PUNTO FUNCIONANDO NOARP MULTICAST MTU:1500 Métrica:1 Paquetes RX:6384 errores:30 perdidos:0 overruns:0 frame:0 Paquetes TX:6893 errores:0 perdidos:0 overruns:0 carrier:0 colisiones:0 long.colaTX:3 Bytes RX:5473081 (5.4 MB) TX bytes:974316 (974.3 KB) wlan0 Link encap:Ethernet direcciónHW 00:26:4d:c3:d0:44 DIFUSIÓN MULTICAST MTU:1500 Métrica:1 Paquetes RX:0 errores:0 perdidos:0 overruns:0 frame:0 Paquetes TX:0 errores:0 perdidos:0 overruns:0 carrier:0 colisiones:0 long.colaTX:1000 Bytes RX:0 (0.0 B) TX bytes:0 (0.0 B) note.-it is logical all the counters are cero if the wireless device is down root@zorrillo:/home/zorrillo/Descargas/802BGA# ifconfig wlan0 up SIOCSIFFLAGS: Operation not possible due to RF-kill root@zorrillo:/home/zorrillo/Descargas/802BGA# It would seem the wireless switching does not react with whichever ubuntu 11.04 command (I hope to be wrong). The target remains the same, in order of the scripts above. I am worried, I have tried to find any answer for days and nights. Toshiba does not supply drivers or soft support for linux, marketing of course. I only see the device is up by protocols and down phisically, My question is, is it possible to enable or not shutdown physically the device?, because in the toshiba model nb255 the wifi is not set up/down bye means of a physical switch, but by means a combination of Fn + F8 (only for windows 7, no one more), Is there one possibility to configure the hot keys in ubuntu?

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  • 'Unable to mount Filesystem' Error

    - by Charles
    Trying to extract data from a 'bricked' Western Digital MyBook Live 2tb drive. I came across a forum that advised to use Ubuntu (booted from a CD) on my Macbook. Managed to download and create a boot CD for Ubuntu (like this little operating system btw). Booted the machine with the CD and plugged the drive (which I had extracted from it's casing and placed into a external USB SATA case & plugged to the laptop). The drive is seen by Ubuntu but each time I click on the drive, it gives me the following error: Unable to mount 2.0 TB Filesystem Error mounting: mount: wrong fs type, bad option, bad superblock on /dev/sdb4, missing codepage or helper program, or other error In some cases useful info is found in syslog -try dmesg | tail or so I am new to this and spent quite some time searching this site to see if I could find a solution to this problem without troubling anyone. I came up with a few that came close but some of the questioners mentioned that they had lost data...which scared me from going further. I need to basically extract 1 particular folder from the drive. If I can get to mount this volume 'sdb4', there is a folder called 'My_Work' which I need to back up. The rest I have/had a copy of. When I typed in dmesg | tail...I got several lines..but I think ones that are relevant are: [ 406.864677] EXT4-fs (sdb4): bad block size 65536 [ 429.098776] hfs: write access to a journaled filesystem is not supported, use the force option at your own risk, mounting read-only [ 439.786365] hfs: write access to a journaled filesystem is not supported, use the force option at your own risk, mounting read-only [ 445.982692] EXT4-fs (sdb4): bad block size 65536 [ 1565.841690] EXT4-fs (sdb4): bad block size 65536 I read somewhere to try/check 'sudo fdisk -l /dev/sdb4'. It gave me the following result: Disk /dev/sdb44: 1995.8 GB, 1995774623744 bytes 255 heads, 63 sectors/track, 242639 cylinders, total 3897997312 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/sdb4 doesn't contain a valid partition table This is where I reached and got frustrated and decided to try & get help on this without digging myself deeper into a hole! I understand that the answer may already be out there. If so, could someone please point me in the right direction. And if not, could someone please resolve (if possible) my situation!

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  • 13.10 upgrade dropping wifi [on hold]

    - by Daryl
    Almost a complete newb here. After my last upgrade from 12.04 to 13.10 my wifi now randomly drops. The only way I can get a signal back is a shutdown and restart otherwise it shows no network is even available to connect to. Had no problems until the upgrade. Any help would be appreciated. H/W path Device Class Description ==================================================== system h8-1534 (H2N64AA#ABA) /0 bus 2AC8 /0/0 memory 64KiB BIOS /0/4 processor AMD FX(tm)-6200 Six-Core Processor /0/4/5 memory 288KiB L1 cache /0/4/6 memory 6MiB L2 cache /0/4/7 memory 8MiB L3 cache /0/d memory 10GiB System Memory /0/d/0 memory DIMM Synchronous [empty] /0/d/1 memory 4GiB DIMM DDR3 Synchronous 1600 MHz (0.6 ns) /0/d/2 memory 2GiB DIMM DDR3 Synchronous 1600 MHz (0.6 ns) /0/d/3 memory 4GiB DIMM DDR3 Synchronous 1600 MHz (0.6 ns) /0/100 bridge RD890 PCI to PCI bridge (external gfx0 port B) /0/100/0.2 generic RD990 I/O Memory Management Unit (IOMMU) /0/100/2 bridge RD890 PCI to PCI bridge (PCI express gpp port B) /0/100/2/0 display Turks PRO [Radeon HD 7570] /0/100/2/0.1 multimedia Turks/Whistler HDMI Audio [Radeon HD 6000 Series] /0/100/5 bridge RD890 PCI to PCI bridge (PCI express gpp port E) /0/100/5/0 bus TUSB73x0 SuperSpeed USB 3.0 xHCI Host Controller /0/100/11 storage SB7x0/SB8x0/SB9x0 SATA Controller [RAID5 mode] /0/100/12 bus SB7x0/SB8x0/SB9x0 USB OHCI0 Controller /0/100/12.2 bus SB7x0/SB8x0/SB9x0 USB EHCI Controller /0/100/13 bus SB7x0/SB8x0/SB9x0 USB OHCI0 Controller /0/100/13.2 bus SB7x0/SB8x0/SB9x0 USB EHCI Controller /0/100/14 bus SBx00 SMBus Controller /0/100/14.2 multimedia SBx00 Azalia (Intel HDA) /0/100/14.3 bridge SB7x0/SB8x0/SB9x0 LPC host controller /0/100/14.4 bridge SBx00 PCI to PCI Bridge /0/100/14.5 bus SB7x0/SB8x0/SB9x0 USB OHCI2 Controller /0/100/15 bridge SB700/SB800/SB900 PCI to PCI bridge (PCIE port 0) /0/100/15.1 bridge SB700/SB800/SB900 PCI to PCI bridge (PCIE port 1) /0/100/15.2 bridge SB900 PCI to PCI bridge (PCIE port 2) /0/100/15.2/0 wlan0 network RT3290 Wireless 802.11n 1T/1R PCIe /0/100/15.2/0.1 generic RT3290 Bluetooth /0/100/15.3 bridge SB900 PCI to PCI bridge (PCIE port 3) /0/100/15.3/0 eth0 network RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller /0/100/16 bus SB7x0/SB8x0/SB9x0 USB OHCI0 Controller /0/100/16.2 bus SB7x0/SB8x0/SB9x0 USB EHCI Controller /0/101 bridge Family 15h Processor Function 0 /0/102 bridge Family 15h Processor Function 1 /0/103 bridge Family 15h Processor Function 2 /0/104 bridge Family 15h Processor Function 3 /0/105 bridge Family 15h Processor Function 4 /0/106 bridge Family 15h Processor Function 5 /0/1 scsi0 storage /0/1/0.0.0 /dev/sda disk 1TB WDC WD1002FAEX-0 /0/1/0.0.0/1 volume 189MiB Windows FAT volume /0/1/0.0.0/2 /dev/sda2 volume 244MiB data partition /0/1/0.0.0/3 /dev/sda3 volume 931GiB LVM Physical Volume /0/2 scsi2 storage /0/2/0.0.0 /dev/cdrom disk DVD A DH16ACSHR /0/3 scsi6 storage /0/3/0.0.0 /dev/sdb disk SCSI Disk /0/3/0.0.1 /dev/sdc disk SCSI Disk /0/3/0.0.2 /dev/sdd disk SCSI Disk /0/3/0.0.3 /dev/sde disk MS/MS-Pro /0/3/0.0.3/0 /dev/sde disk /1 power Standard Efficiency I apologize for my newbness. I hope this is enough info for the hardware. Thanks Bruno for pointing out I needed to add more info. If I am lacking anything else please let me know and I'll post it.

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  • JavaOne 2013: (Key) Notes of a conference – State of the Java platform and all the roadmaps by Amis

    - by JuergenKress
    Last week’s JavaOne conference provided insights in the roadmap of the Java platform as well as in the current state of things in the Java community. The close relationship between Oracle and IBM concerning Java, the (continuing) lack of such a relationship with Google, the support from Microsoft for Java applications on its Azure cloud and the vibrant developer community – with over 200 different Java User Groups in many countries of the world. There were no major surprises or stunning announcements. Java EE 7 (release in June) was celebrated, the progress of Java 8 SE explained as well as the progress on Java Embedded and ME. The availability of NetBeans 7.4 RC1 and JDK 8 Early Adopters release as well as the open sourcing of project Avatar probably were the only real news stories. The convergence of JavaFX and Java SE is almost complete; the upcoming alignment of Java SE Embedded and Java ME is the next big consolidation step that will lead to a unified platform where developers can use the same skills, development tools and APIs on EE, SE, SE Embedded and ME development. This means that anything that runs on ME will run on SE (Embedded) and EE – not necessarily the reverse because not all SE APIs are part of the compact profile or the ME environment. However, the trimming down of the SE libraries and the increased capabilities of devices mean that a pretty rich JVM runs on many devices – such as JavaFX 8 on the Raspberry PI. The major theme of the conference was Internet of Things. A world of things that are smart and connected, devices like sensors, cameras and equipment from cars, fridges and television sets to printers, security gates and kiosks that all run Java and are all capable of sending data over local network connections or directly over the internet. The number of devices that has these capabilities is rapidly growing. This means that the number of places where Java programs can help program the behavior of devices is growing too. It also means that the volume of data generated is expanding and that we have to find ways to harvest that data, possibly do a local pre-processing (filter, aggregate) and channel the data to back end systems. Terms typically used are edge devices (small, simple, publishing data), gateways (receiving data from many devices, collecting and consolidating, pre-processing, sending onwards to back end – typically using real time event processing) and enterprise services – receiving the data-turned-information from the gateways to further consolidate, distribute and act upon. A cheap device like the Raspberry PI is a perfect way to get started as a Java developer with what embedded (device) programming means and how interaction with physical input and output takes place. Roadmaps The over all progress on Java is visualized in this overview: Read the full article here. WebLogic Partner Community For regular information become a member in the WebLogic Partner Community please visit: http://www.oracle.com/partners/goto/wls-emea ( OPN account required). If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Mix Forum Wiki Technorati Tags: Amis,OOW,Oracle OpenWorld,JavaOne,WebLogic,WebLogic Community,Oracle,OPN,Jürgen Kress

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  • In-Store Tracking Gets a Little Harder

    - by David Dorf
    Remember how Nordstrom was tracking shopper movements within their stores using the unique number, called a MAC, emitted by the WiFi radio in smartphones?  The phones didn't need to connect to the network, only have their WiFi enabled, as most people do by default.  They did this, presumably, to track shoppers' path to purchase and better understand traffic patterns.  Although there were signs explaining this at the entrances, people didn't like the notion of being tracked.  (Nevermind that there are cameras in the ceiling watching them.)  Nordstrom stopped the program. To address this concern the Future of Privacy, a Washington think tank, created Smart Store Privacy, a do-not-track service that allows consumers to register their MAC address in much the same way people register their phone numbers in the national do-not-call list.  A group of companies agreed to respect consumers' wishes and ignore smartphones listed in the database.  The database includes Bluetooth identifiers as well.  Of course you could simply turn your bluetooth and WiFi off when shopping as well. Most know that Apple prefers to use BLE beacons to contact and track smartphones within their stores.  This feature extends the typical online experience to also work in physical stores.  By identifying themselves, shoppers can expect a more tailored shopping experience much like what we've come to expect from Amazon's website, with product recommendations and offers that are (usually) relevant. But the upcoming release of iOS8 is purported to have a new feature that randomizes the WiFi MAC address of smartphones during the "probing" phase.  That is, before connecting to the WiFi network, a random MAC number is used so as to keep the smartphone's real MAC address secret.  Unless you actually connect to the store's WiFi, they won't recognize the MAC address. The details on this are still sketchy, but if the random MAC is consistent for a short period, retailers will still be able to track movements anonymously, but they won't recognize repeat visitors.  That may be sufficient for traffic analytics, but it will stymie target marketing.  In the case of marketing, using iBeacons with opt-in permission from consumers will be the way forward. There is always a battle between utility and privacy, so I expect many more changes in this area.  Incidentally, if you'd like to see where beacons are being used this site tracks them around the world.

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  • vJUG: Worldwide Virtual JUG Created

    - by Tori Wieldt
    London Java Community leader and technical evangelist Simon Maple has created a Meetup called vJUG, with aim toward connecting Java Developers in the virtual world. The aim for vJUG is: Get technical leaders from around the world to present to the vJUG members (without travel cost concerns!). Work with local JUGs to provide worldwide content to their members and help JUGs present to a worldwide audience. Provide content to devs without access to a local JUG. Be a hub that will stream content from other JUG sessions live.  The vJUG is not intended to replace local JUG efforts. "The vJUG can never be, and will never be, as vibrant and valuable to its members as a proper local JUG can. Why? Because the true value in JUG meetings are the face to face interactions and personal networking," said Maple. "However, many people do not have access to a really active JUG with great speakers and awesome content. Or, like me, the closest JUG is about 90 mins away." WebEx and Google Hangouts are great, Maple explained, he hopes vJUG will provide more coordination of online events.  Maple hopes that in the future, vJUG will provide An Events calendar with reminders and links to up coming meetings. A Newsletter with what's coming up and links to previous sessions. Coordination of links to IRC channels which are active during presentations (to create a feeling of virtual community). Comments and forums around sessions and presentations A place where physical JUGs could advertise their sessions (i.e. a NY JUG event) to a worldwide audience, when streamed, via an event that people can sign up to. A common Webex or Hangout. Maple encourages both people who need a JUG and existing JUG members to join vJUG. "I'm looking forward to talking with many of you one to get members, speakers, and JUG support!" Join vJUG now! (I sense a need for a logo...) 

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  • Weird Ubuntu Desktop Boot Partition On External Hard Drive

    - by Magnitus
    I have a Thinkpad with Windows 7. Last time I installed an Ubuntu/Windows dual boot, Windows was never same after and regularly got corrupted so this time, I installed Ubuntu on a separate external hard drive. I took a 500 GB external hard drive and used Windows to shrink the partition on it to 400 GB, freeing 100 GB to install Ubuntu. Then I modified the booting priority of my computer to boot from the external hard drive if present. Then, I installed Ubuntu desktop on the external hard drive using a DVD, picked the most simplistic partitioning scheme I could get away with (didn't go auto as it didn't include the external hard drive as a choice) and voilà. Fast forward some time and I'm trying to refresh my understanding of Linux partitions to install a bunch of servers, so I'm looking at the current partitioning scheme on my external hard drive and find the boot partition puzzling... sda is my integrated hard drive with Windows 7. sdb is my Ubuntu desktop external hard drive. Running parted on sdb, I get this: (parted) print Model: WD My Passport 0740 (scsi) Disk /dev/sdb: 500GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 1049kB 393GB 393GB primary ntfs boot 2 393GB 500GB 107GB extended 5 393GB 425GB 32.8GB logical linux-swap(v1) 6 425GB 500GB 74.6GB logical ext4 At this point, I'm wondering why the ntfs partition is flagged as "boot" and not my ext4 partition which is the partition that contains / (and by extension, /boot since it's not on its own separate partition). Looking at mtab only confirms what I already know: eric@eric-ThinkPad-W530:~$ sudo cat /etc/mtab /dev/sdb6 / ext4 rw,errors=remount-ro 0 0 proc /proc proc rw,noexec,nosuid,nodev 0 0 sysfs /sys sysfs rw,noexec,nosuid,nodev 0 0 none /sys/fs/cgroup tmpfs rw 0 0 none /sys/fs/fuse/connections fusectl rw 0 0 none /sys/kernel/debug debugfs rw 0 0 none /sys/kernel/security securityfs rw 0 0 udev /dev devtmpfs rw,mode=0755 0 0 devpts /dev/pts devpts rw,noexec,nosuid,gid=5,mode=0620 0 0 tmpfs /run tmpfs rw,noexec,nosuid,size=10%,mode=0755 0 0 none /run/lock tmpfs rw,noexec,nosuid,nodev,size=5242880 0 0 none /run/shm tmpfs rw,nosuid,nodev 0 0 none /run/user tmpfs rw,noexec,nosuid,nodev,size=104857600,mode=0755 0 0 none /sys/fs/pstore pstore rw 0 0 systemd /sys/fs/cgroup/systemd cgroup rw,noexec,nosuid,nodev,none,name=systemd 0 0 gvfsd-fuse /run/user/1000/gvfs fuse.gvfsd-fuse rw,nosuid,nodev,user=eric 0 0 /dev/sdb1 /media/eric/My\040Passport fuseblk rw,nosuid,nodev,allow_other,default_permissions,blksize=4096 0 0 My lack of understanding concerning this is not vital to anything (this is only my development desktop partition), but somehow annoys me. Any insight that could shed some light on this would be welcome.

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  • Why doesn't Ubuntu detect my second hard drive?

    - by user93179
    I am new to Linux and to Ubuntu, I was wondering, I have two hard drives setup in SATA ports (non-raid, at least I don't think they are). I installed ubuntu unto the drives fresh without any previous versions or windows at all. However when I got the Ubuntu 12.04 LTS working, all I see is 1 x 120 gigabyte harddrive. Also, not sure if this is important or not, my hard drives are SSD. My computer specs are Asus P9Z77-V-LK Nvidia Geforce GTX 660 TI Intel i5 3570k 3.4 /proc/partitions shows: major minor #blocks name 8 0 117220824 sda 8 1 117219328 sda1 8 16 117220824 sdb 8 17 96256 sdb1 8 18 108780544 sdb2 8 19 8342528 sdb3 11 0 1048575 sr0 and ls -l /sys/block/ | grep -v /virtual/: lrwxrwxrwx 1 root root 0 Sep 27 17:26 sda - ../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda lrwxrwxrwx 1 root root 0 Sep 27 17:26 sdb - ../devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0/block/sdb lrwxrwxrwx 1 root root 0 Sep 27 22:26 sdc - ../devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1/1-1.1:1.0/host6/target6:0:0/6:0:0:0/block/sdc lrwxrwxrwx 1 root root 0 Sep 27 22:04 sr0 - ../devices/pci0000:00/0000:00:1f.2/host3/target3:0:0/3:0:0:0/block/sr0 sudo file -s /dev/sd*: /dev/sda: x86 boot sector; partition 1: ID=0x7, starthead 32, startsector 2048, 234438656 sectors, code offset 0xc0, OEM-ID " ?", Bytes/sector 190, sectors/cluster 124, reserved sectors 191, FATs 6, root entries 185, sectors 64514 (volumes 32 MB) , physical drive 0x7e, dos 32 MB) , FAT (32 bit), sectors/FAT 749, reserved3 0x800000, serial number 0x35361a2b, unlabeled /dev/sdb2: Linux rev 1.0 ext4 filesystem data, UUID=387761ac-5eba-4d0f-93ba-746a82fb541d (needs journal recovery) (extents) (large files) (huge files) /dev/sdb3: data /dev/sdc: x86 boot sector; partition 1: ID=0xc, active, starthead 0, startsector 8064, 30473088 sectors, code offset 0xc0 /dev/sdc1: x86 boot sector, code offset 0x58, OEM-ID "SYSLINUX", sectors/cluster 64, reserved sectors 944, Media descriptor 0xf8, heads 128, hidden sectors 8064, sectors 30473088 (volumes 32 MB) , FAT (32 bit), sectors/FAT 3720, Backup boot sector 8, serial number 0xf90c12e9, label: "KINGSTON " /dev/sda1: x86 boot sector, code offset 0x52, OEM-ID "NTFS ", sectors/cluster 8, reserved sectors 0, Media descriptor 0xf8, heads 255, hidden sectors 2048, dos 32 MB) , FAT (32 bit), sectors/FAT 749, reserved3 0x800000, serial number 0x35361a2b, unlabeled Any help would be greatly appreciated! Thanks Another thing I noticed is, when i use gparted to locate my drives, it seems that sda1 is my second drive that I am not detecting when I boot up and my ubuntu + FAT Boot files are installed in sdb1

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  • Raid superblock missing on single parition. Recovery needed!

    - by user171639
    Ok so I have a 2 TB raid 1 setup that has three partitions: sdc1: linux sdc2: swap sdc3: LVM for data However the LVM will no longer mount. So I thought that I would take the first drive, mount it in linux (ive done this b4), and reset the spare drive to copy the data. Normally I can mount a single drive for data recovery using: sudo su apt-get install mdadm lvm2 mdadm --assemble --scan modprobe dm-mod vgscan vgchange -ay c mount -o ro /dev/c/c /mnt Unfortunately, vgscan doesnot recognize the data partition. It appears as though the superblock on the first drive's data partition was erased while syncing with the second. So now I cannot mount that partition and the second drive is stuck in spare mode. Any ideas? Or a way to force mount the data partition just to copy the data? knoppix@Microknoppix:~$ sudo su root@Microknoppix:/home/knoppix# apt-get install mdadm lvm2 Reading package lists... Done Building dependency tree Reading state information... Done lvm2 is already the newest version. mdadm is already the newest version. 0 upgraded, 0 newly installed, 0 to remove and 551 not upgraded. root@Microknoppix:/home/knoppix# mdadm --assemble --scan mdadm: /dev/md/1 has been started with 1 drive (out of 2). mdadm: /dev/md/0 has been started with 1 drive (out of 2). root@Microknoppix:/home/knoppix# modprobe dm-mod root@Microknoppix:/home/knoppix# vgscan Reading all physical volumes. This may take a while... No volume groups found root@Microknoppix:/home/knoppix# cat /proc/mdstat Personalities : [raid1] md0 : active raid1 sdc1[2] 4193268 blocks super 1.2 [2/1] [U_] md1 : active raid1 sdc2[2] 524276 blocks super 1.2 [2/1] [U_] unused devices: <none> root@Microknoppix:/home/knoppix# mdadm -v --assemble --auto=yes /dev/md2 /dev/sdc3 mdadm: looking for devices for /dev/md2 mdadm: no recogniseable superblock on /dev/sdc3 mdadm: /dev/sdc3 has no superblock - assembly aborted root@Microknoppix:/home/knoppix# dumpe2fs /dev/md0 | grep -i superblock dumpe2fs 1.42.4 (12-Jun-2012) Primary superblock at 0, Group descriptors at 1-1 Backup superblock at 32768, Group descriptors at 32769-32769 Backup superblock at 98304, Group descriptors at 98305-98305 Backup superblock at 163840, Group descriptors at 163841-163841 Backup superblock at 229376, Group descriptors at 229377-229377 Backup superblock at 294912, Group descriptors at 294913-294913 Backup superblock at 819200, Group descriptors at 819201-819201 Backup superblock at 884736, Group descriptors at 884737-884737 root@Microknoppix:/home/knoppix# Notes: I can read the super block from the spare drive. I was gonna try and restore the superblock from one of the backups, but i dont know how or if this would work. I also heard creating a new array (mdadm --create) using the same parameters will not delete the data on the drive but i didnt want to risk it. Recommendations?

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  • What do you need to know to be a world-class master software developer? [closed]

    - by glitch
    I wanted to bring up this question to you folks and see what you think, hopefully advise me on the matter: let's say you had 30 years of learning and practicing software development in front of you, how would you dedicate your time so that you'd get the biggest bang for your buck. What would you both learn and work on to be a world-class software developer that would make a large impact on the industry and leave behind a legacy? I think that most great developers end up being both broad generalists and specialists in one-two areas of interest. I'm thinking Bill Joy, John Carmack, Linus Torvalds, K&R and so on. I'm thinking that perhaps one approach would be to break things down by categories and establish a base minimum of "software development" greatness. I'm thinking: Operating Systems: completely internalize the core concepts of OS, perhaps gain a lot of familiarity with an OSS one such as Linux. Anything from memory management to device drivers has to be complete second nature. Programming Languages: this is one of those topics that imho has to be fully grokked even if it might take many years. I don't think there's quite anything like going through the process of developing your own compiler, understanding language design trade-offs and so on. Programming Language Pragmatics is one of my favorite books actually, I think you want to have that internalized back to back, and that's just the start. You could go significantly deeper, but I think it's time well spent, because it's such a crucial building block. As a subset of that, you want to really understand the different programming paradigms out there. Imperative, declarative, logic, functional and so on. Anything from assembly to LISP should be at the very least comfortable to write in. Contexts: I believe one should have experience working in different contexts to truly be able to appreciate the trade-offs that are being made every day. Embedded, web development, mobile development, UX development, distributed, cloud computing and so on. Hardware: I'm somewhat conflicted about this one. I think you want some understanding of computer architecture at a low level, but I feel like the concepts that will truly matter will be slightly higher level, such as CPU caching / memory hierarchy, ILP, and so on. Networking: we live in a completely network-dependent era. Having a good understanding of the OSI model, knowing how the Web works, how HTTP works and so on is pretty much a pre-requisite these days. Distributed systems: once again, everything's distributed these days, it's getting progressively harder to ignore this reality. Slightly related, perhaps add solid understanding of how browsers work to that, since the world seems to be moving so much to interfacing with everything through a browser. Tools: Have a really broad toolset that you're familiar with, one that continuously expands throughout the years. Communication: I think being a great writer, effective communicator and a phenomenal team player is pretty much a prerequisite for a lot of a software developer's greatness. It can't be overstated. Software engineering: understanding the process of building software, team dynamics, the requirements of the business-side, all the pitfalls. You want to deeply understand where what you're writing fits from the market perspective. The better you understand all of this, the more of your work will actually see the daylight. This is really just a starting list, I'm confident that there's a ton of other material that you need to master. As I mentioned, you most likely end up specializing in a bunch of these areas as you go along, but I was trying to come up with a baseline. Any thoughts, suggestions and words of wisdom from the grizzled veterans out there who would like to share their thoughts and experiences with this? I'd really love to know what you think!

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  • The long road to bug-free software

    - by Tony Davis
    The past decade has seen a burgeoning interest in functional programming languages such as Haskell or, in the Microsoft world, F#. Though still on the periphery of mainstream programming, functional programming concepts are gradually seeping into the imperative C# language (for example, Lambda expressions have their root in functional programming). One of the more interesting concepts from functional programming languages is the use of formal methods, the lofty ideal behind which is bug-free software. The idea is that we write a specification that describes exactly how our function (say) should behave. We then prove that our function conforms to it, and in doing so have proved beyond any doubt that it is free from bugs. All programmers already use one form of specification, specifically their programming language's type system. If a value has a specific type then, in a type-safe language, the compiler guarantees that value cannot be an instance of a different type. Many extensions to existing type systems, such as generics in Java and .NET, extend the range of programs that can be type-checked. Unfortunately, type systems can only prevent some bugs. To take a classic problem of retrieving an index value from an array, since the type system doesn't specify the length of the array, the compiler has no way of knowing that a request for the "value of index 4" from an array of only two elements is "unsafe". We restore safety via exception handling, but the ideal type system will prevent us from doing anything that is unsafe in the first place and this is where we start to borrow ideas from a language such as Haskell, with its concept of "dependent types". If the type of an array includes its length, we can ensure that any index accesses into the array are valid. The problem is that we now need to carry around the length of arrays and the values of indices throughout our code so that it can be type-checked. In general, writing the specification to prove a positive property, even for a problem very amenable to specification, such as a simple sorting algorithm, turns out to be very hard and the specification will be different for every program. Extend this to writing a specification for, say, Microsoft Word and we can see that the specification would end up being no simpler, and therefore no less buggy, than the implementation. Fortunately, it is easier to write a specification that proves that a program doesn't have certain, specific and undesirable properties, such as infinite loops or accesses to the wrong bit of memory. If we can write the specifications to prove that a program is immune to such problems, we could reuse them in many places. The problem is the lack of specification "provers" that can do this without a lot of manual intervention (i.e. hints from the programmer). All this might feel a very long way off, but computing power and our understanding of the theory of "provers" advances quickly, and Microsoft is doing some of it already. Via their Terminator research project they have started to prove that their device drivers will always terminate, and in so doing have suddenly eliminated a vast range of possible bugs. This is a huge step forward from saying, "we've tested it lots and it seems fine". What do you think? What might be good targets for specification and verification? SQL could be one: the cost of a bug in SQL Server is quite high given how many important systems rely on it, so there's a good incentive to eliminate bugs, even at high initial cost. [Many thanks to Mike Williamson for guidance and useful conversations during the writing of this piece] Cheers, Tony.

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  • From 20,663 issues to 1 issue&ndash;style-copping C5.Tests

    - by TATWORTH
    Originally posted on: http://geekswithblogs.net/TATWORTH/archive/2014/05/28/from-20663-issues-to-1-issuendashstyle-copping-c5.tests.aspxI recently became interested in the potential of the C5 Collections solution from http://www.itu.dk/research/c5/, however I was dismayed at the state of the code in the unit test project, so I set about fixing the 20,663 issues detected by StyleCop. The tools I used were the latest versions of: My 64-bit development PC running Windows 8 Update with 8Gb RAM Visual Studio 2013 Ultimate with SP2 ReSharper GhostDoc Pro My first attempt had to be abandoned due to collision of class names which broke one of the unit tests. So being aware of this duplication of class names, I started again and planned to prepend the class names with the namespace name. In some cases I additionally prepended the item of the C5 collection that was being tested. So what was the condition of code at the start? Besides the sprawl of C# code not written to style cop standard, there was: 1) Placing of many classes within one physical file. 2) Namespace within name space that did not follow the project structure. 3) As already mentioned, duplication of class names across namespaces. 4) A copyright notice that spawled but had to be preserved. 5) Project sub-folders were all lower case instead of initial letter capitalised. The first step was to add a stylecop heading plus the original heading contained within a region, to every file. The next step was to run GhostDoc Pro using its “Document File” option on every file but not letting it replace the headers, I had added. This brought the number of issues down to 18,192. I then went through each file collapsing each class and prepending names as appropriate. At each step, I saved the changes to my local Git. The step was to move each class to its own file and to style-cop each file. ReSharper provides a very useful feature for doing this which also fixes missing “this.” and moves using statements inside the namespace. Some classes required minimal work whereas others required extensive work to reach the stylecop standard. The unit tests were run at each split and when each class was completed. When all was done, one issue remained which I will need to submit to stylecop team for their advice (and possibly a fix to stylecop). The updated solution has been made available at https://c5stylecopped.codeplex.com/releases/view/122785.

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  • Misused mke2fs and cannot boot into system

    - by surlogics
    I installed Ubuntu with WUBI in Windows 7 64bit, and I had installed Mandriva 2011 with a disk. I tried to learn Linux with Ubuntu and misused mke2fs; after I reboot my computer, Windows 7 and Ubuntu has crashed. As I have Mandriva, I boot into Mandriva and found # df -h /dev/sda7 12G 9.8G 1.5G 88% / /dev/sda2 15G 165M 14G 2% /media/logical /dev/sda6 119G 88G 32G 74% /media/2C9E85319E84F51C /dev/sda5 118G 59G 60G 50% /media/D25A6DDE5A6DBFB9 /dev/sda9 100G 188M 100G 1% /media/ae69134a-a65e-488f-ae7f-150d1b5e36a6 /dev/sda1 100M 122K 100M 1% /media/DELLUTILITY /dev/sda3 98G 81G 17G 83% /media/OS # fdisk /dev/sda Command (m for help): p Disk /dev/sda: 500.1 GB, 500107862016 bytes 255 heads, 63 sectors/track, 60801 cylinders, total 976773168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xd24f801e Device Boot Start End Blocks Id System /dev/sda1 2048 206847 102400 6 FAT16 /dev/sda2 * 206848 30926847 15360000 7 HPFS/NTFS/exFAT /dev/sda3 30926848 235726847 102400000 7 HPFS/NTFS/exFAT /dev/sda4 235728864 976771071 370521104 f W95 Ext'd (LBA) /dev/sda5 235728896 481488895 122880000 7 HPFS/NTFS/exFAT /dev/sda6 727252992 976771071 124759040 7 HPFS/NTFS/exFAT /dev/sda7 481500243 506674034 12586896 83 Linux /dev/sda8 506674098 514851119 4088511 82 Linux swap / Solaris /dev/sda9 514851183 727246484 106197651 83 Linux Partition table entries are not in disk order I think I may used the following command mke2fs -j -L "logical"/dev/sda2 but I had forgotten what kind of partition it was before I transfered it into ext3. perhaps ntfs Data was not lost, and I can view my files as I could in Windows. In Mandriva, there are following disks: 117.2 GB hard disk, files in it is the same as my Windows D:, and Ubuntu was installed in it; 119.0 GB hard disk is my G:, with my personal files in it; 12.0 GB is the same with Mandriva / (with means root), 101.3 GB hard disk with nothing but lost+found; DELLUTILITY should be Dell computer utilities pre-installed in my computer; logical is the disk which I had spoiled, I can view nothing but lost+found; and OS is the C: in my Windows. After I boot, grub lets me choose Mandriva or Windows. I chose Windows and it tells me: FILE system type unknown, partition type 0x7 Error 13: Invalid or unsupported executable format I doubt something wrong with windows MBR or something # cat /boot/grub/menu.lst timeout 5 color black/cyan yellow/cyan gfxmenu (hd0,6)/boot/gfxmenu default 0 title linux kernel (hd0,6)/boot/vmlinuz BOOT_IMAGE=linux root=UUID=199581b7-ac7e-4c5f-9888-24c4f213cad8 nokmsboot logo.nologo quiet resume=UUID=34c546e4-9c42-4526-aa64-bbdc0e9d64fd splash=silent vga=788 initrd (hd0,6)/boot/initrd.img title linux-nonfb kernel (hd0,6)/boot/vmlinuz BOOT_IMAGE=linux-nonfb root=UUID=199581b7-ac7e-4c5f-9888-24c4f213cad8 nokmsboot resume=UUID=34c546e4-9c42-4526-aa64-bbdc0e9d64fd initrd (hd0,6)/boot/initrd.img title failsafe kernel (hd0,6)/boot/vmlinuz BOOT_IMAGE=failsafe root=UUID=199581b7-ac7e-4c5f-9888-24c4f213cad8 nokmsboot failsafe initrd (hd0,6)/boot/initrd.img title windows root (hd0,1) makeactive chainloader +1 I can boot into Linux, but not Ubuntu, it boot into Mandriva. I don't have a boot disk. Help me find a way to make it work again.

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