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  • Motorola India meets Mayan calender dead line – earlier than predicted

    - by Boonei
    My favorite cell phone maker Moto is closing it doors in India. Plan is to  have their service shops open. If you still want to grab the last living decendent of the phone in India there is good news “would continue to sell its phones till stocks are exhausted while service centers would continue to function”. Ya !  lock up in your safe, wait 20 years, then sell this antique for a fortune. There is will be staff cut and Moto promised to help employees at these difficult times. India is one of the most sort out market for mobile makers, what is running in Googles mind ? May be world is falling apart like Mayans predicted ?    

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  • Now Instagram lets you record and share 15 seconds video with awesome filters

    - by Gopinath
    Instagram is one of the most popular photo sharing applications and it is very popular for amazing filters that turn an ordinary photo in to an incredible one. Today Instagram extended the filters and sharing options to videos. With the latest version of Instagram application for iOS/Android you can record videos, apply filters and share them. Recording and sharing videos on Instagram is much similar to photos and. You can capture videos up to 15 seconds and there are 13 filters to choose for processing. Wondering why the limit is at 15 seconds? Pundits are saying that TV ads are in general 15 seconds and Instagram is preparing for video ads in near future. Anyways within hours of video sharing features, Instagram is flooded with short videos and the Explore section has very interesting ones to browse through. Just like photos, you can share the captured videos to your Twitter, Facebook and other social stream from Instagram.

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  • Set iPhone Style Location Based Alerts On Your Android Device With Google Now

    - by Gopinath
    Location based alerts of iPhone are very useful. You can set an alert to popup as soon as you reach a specific location like “Pickup milk and eggs” when I’m near a grocery store. This feature was missing in Android for a long time, but last week at Google I/O conference Google released an update to Google Now which supports location based alerts. To setup a location based alert 1. Launch Google Now 2. Type or say add reminder 3. By default it shows time based alert interface, switch it location based by touching Location icon 4. Set reminder text, choose a location and touch Set reminder 5. Your alert is set now and as soon as you are close by the specified location, you’ll see an alert on your device. This is a nice feature and I’m using it quite often for the past couple of days.  There are couple of things missing from the current version of Google Now location based alerts– recurring alerts and ability to set alerts on leaving a specific location. It is not possible to recur location based alerts. You will be alerted only once as soon as you reach the location and it is not possible to repeat the alert next time you visit the location. Lets say you want to be reminded to say hi to friend’s parents whenever you are travelling close by their home. It does not work. The second missing feature is something basic and some how Google did not incorporate in their first iteration. Lets say you are at office now and you want to set up alert to pickup flowers when you leave office. Sounds like a simple use case for location based alerts right? But there is no way to set this type of alerts. Google Now alerts you as soon as you reach a location, but not when you leave a location. Do you have an Android that supports Google Now? If so what are your thoughts on location based alerts?

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  • Empty APN list on your Android phone? Restart the phone to fix it

    - by Gopinath
    Today I tried to connect to internet on my Google Galaxy Nexus running on 4.2.2 using Cellular Data connection and it failed. Tried reaching customer care representative to figure out why data connection is not working, but the robots (Interactive Voice Response systems) never allowed me to reach a human. After digging through the settings I found empty list of APN (Access Point Names) is the reason for not able to connect to internet. Not sure what caused APN list to vanish but I tried to create a new one that matches with the settings required for AT & T mobile. To my surprise I found that the newly created APN is also not shown in the APN list. Well there is something wrong with the phone – my APN’s are not shown as well as the newly created one is also not displayed. A simple Google search on this problem shown many forum discussions list and the solution to resolve the issue is to restart the phone. As soon as I restarted my phone the APN list is automatically populated and I’m able to connect to internet on my mobile.

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  • Where Do You Start Your Day: Facebook Or E-Mail?

    - by Gopinath
    EMails and Facebook are integral part of our digital lives. But where do we start our daily digital life can tell a lot about us, says a research firm. According to a research People who check email first tend to be motivated to interact with brands online for the sake of obtaining deals, promotions, or new product information People who initially check Facebook tend to become fans of brands for entertainment purposes or to show support-not to obtain deals. They’re more likely to seek promotions through email. Here is an info graphics that gives insights where is the first place go on net You can read more finding of the research over here Join us on Facebook to read all our stories right inside your Facebook news feed.

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  • At $20/month Windows Azure host my website with 99.97% uptime

    - by Gopinath
    Couple of years ago a reliable and decent performing Windows hosting was not affordable to many enthusiastic developers who want to try a startup idea or build a hobby site. I tried to start an ASP.NET website few years ago to provide services like – Mobile Tracing, Vehicle Tracing. But due to high cost of Windows hosting I developed those services using PHP (not an easy task for .NET developer) and hosted on them Linux servers.  But with recent evolution of Windows Azure, hosting ASP.NET websites on highly reliable servers is affordable. Today anyone can host a high responsive and available ASP.NET website for just $20/month using Windows Azure. My website coziie.com is running on Windows Azure and serves close to quarter millions visitors a month with 99.97% of uptime and most of the page load times are less than 3 seconds. All I spend to run this website is just around $20, if you translate it to India rupees its roughly Rs.1000. The web sever of coziie.com is powered by a single Extra Small Web role instance and the backend is powered by a SQL Azure instance. Azure is quite impressive to provide 99.97% of uptime. Response times during peak are around 3 seconds and on nomarl loads it is around 1.5 seconds. Here is the report of uptime provided by Royal Pingdom over last one year For just $20/month Windows Azure takes care of the following apart from hosting Patches up Windows OS to the latest version Upgrades ASP.NET to the latest version – coziie.com is running on ASP.NET MVC 3 and soon I’ll upgrade it to ASP.NET MVC 4 Hosts data on latest and best version Sql Server database SQL Azure maintains 3 copies of database and automatically recovers in case of server failures and disasters. I never worry about database backups/restore. Provides staging environment for deploying applications for testing purpose and move them to production – I upgrade  twice a month on average With Windows Azure I no longer focus on server maintenance or data backups. They are taken up by Microsoft team and I just focus on building my website. Wish there is a low cost Linux version of Windows Azure so that I can stop worrying about server maintenance of this blog!! If you are looking for a Windows hosting, look no further than Windows Azure. If you find $20/month is a bit expensive to start with you may explore Azure Website (sort of shared hosted environment) which is free to start with and as your traffic grows you can move to paid hosting.

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  • Coziie.com Diwali giveaway contest–Rs.500/- Flipkart Voucher

    - by Gopinath
    At coziie.com we are running a give away contest to celebrate Diwali with our friends. You can enter the contest to win Rs. 500/- Flipkart voucher by just liking us on Facebook. To participate in the contest follow this link – https://www.facebook.com/coziie/app_152045414852131. We ran a similar contest early July and announced winner on July 26th 2013. This time we will announce the winner on Diwali, November 3rd 2013. So don’t miss the chance to get a gift from us on this Diwali. It take less than two minutes to participate in the contest. Best of luck!!

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  • GMail:Want To Embed Picture In Your Mail? Drag and Drop It

    - by Gopinath
    GMail rolled out a nice & useful feature that makes embedding images into emails very easy. Now you can drag and drop an image on the text area of your GMail compose interface to embed it. From now onwards to insert an Image I’ll go with drag & drop instead of using Insert Image option that allows us to choose an image by navigating through the folders. Wait, This Works Only For Google Chrome Users! This feature work only on Google Chrome browser. At least for now. Firefox, IE users have to wait. Google has promised to provide this feature in all other major browsers, but it’s going to take some time. The other browsers don’t have the ability to support this feature or Google trying to promote Chrome by releasing Chrome only features in their popular products? You decide. You can read more details about this in the official GMail blog post. Join us on Facebook to read all our stories right inside your Facebook news feed.

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  • Kill Android Apps without Task Manager

    - by Gopinath
    Android is for geeks. It best fits for the users who know how to get around sloppy areas and find their way out. If you are an heavy Android user you would have noticed Apps crashing often. A well written App should not crash, if crashes should exit the process gracefully. But unfortunately Google Play has many apps that not only just crash, they hang in a where they don’t respond and you can’t access the application. The only option left to you is to forcefully close them. If you encounter a situation to forcefully close an App you have two options. First one is to use Task Manager application to close them and the second option is use built in Android OS features. Here are the steps to forcefully close an Android App without using Task Manager Step 1: Go to Settings and select Apps Step 2: Switch to All apps tab and select the application you want to close Step 3: Touch on Force Stop button to forcefully close the app That’s the simplest way to forcefully kill Android Apps.

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  • How to shutdown Windows 8 PC without using mouse?

    - by Gopinath
    Windows 8 sports a re-imagined desktop and tablet user interface with touch friendly Metro looks. One of the major changes in Windows 8 for a common users  is the lack of start menu, with which we got friended for more than a decade. On Windows 8 we would be missing it. As there is no start menu in Windows 8, the way you shutdown a Windows 8 computer is a bit different. To shutdown using Mouse, you need to hover on the top right edge of the screen to open the hidden menu,  go to "Settings"  tab -> "Power" -> Then choose for "Shut down", "Sleep" or "Restart".  That’s a lot of Mouse movement work and if you are a power user then you may not like to do that. How about shutting down the PC using Keyboard? Here are the two ways to shutdown the PC using keyboard Keyboard shortcuts With the help of keyboard shortcuts you can navigate to Power options of Windows 8. Press Win + C to bring the Settings Charm and use Arrows and Enter keys to navigate to access Shutdown menu. This is one of the easiest way to shutdown the PC without using Mouse. Run Command If you don’t like to go through the Setting menu, you can use the traditional Run commands. Press Win + R to open Run dialog and enter the command shutdown -s -t 0 to immediately shutdown the PC.

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  • Item missing/damaged from Amazon order? Steps to quickly contact support to get replacements

    - by Gopinath
    I ordered few items from Amazon.com last week and when the package is delivered I found an item is missing. I reached out to Amazon Customer care and they resolved the issue by resending the missing item. Amazon’s customer care is awesome! They just asked me few questions regarding the order, person who accepted the delivery and without any further delay they provided details on when I’ll get the replacement item. Best part is Amazon customer care support is available through email, chat & telephone. I chose support through a chat session and resolved the issue. If you also missed an item or found a damaged item then here are the steps to be followed to get a replacement item Step 1 -  Go to amazon.com/contact Step 2 -  Click on Contact Us button available in General Support section, you may have to provide authentication details Step 3 – Contact Us screen displays your recent order. If your query is related to the displayed order then proceed go to next step otherwise select your order by clicking on Choose Different Order button Step 4 – Select the missing/damaged items from the list of items displayed from your order Step 5 – Choose the issue with your order. In case if an item is missing you may want to choose “Problem with an order”, “Missing item or parts” and “Entire item missing from shipment”. You may want to choose the options that are close to the issue you are facing with your order Step 6 – Choose how you want to support. You can choose either “E-Mail”, “Phone” or “Chat”. Based on the selected Support mode, proceed and communicate to them about the issue.  Rest assured. They will resolve your issue quickly.

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  • Google accidentally revealed Nexus 5 phone in Android Kitkat launch video

    - by Gopinath
    Today Google officially announced KitKat as the name of the next version of Android OS(v4.4). They posted a video to showcase the unveiling of the KitKat statue at the company’s headquarters, but they accidentally revealed much more. 9to5Google spotted an unreleased Android smartphone in the video and they posted screen grabs of Googlers using it to take photos. This unreleased phone could be the next version of Google Nexus phone. Google few days ago reduced price of Nexus 4 smartphones by $100 and 8 GB version is reported out of inventory. With all these signs it seems to be clear that it is just weeks away for the launch of Google Nexus smartphone. Soon after the news of leaked smartphone spread on blogs, Google pulled Kitkat launch video to private. But few bloggers managed to save a copy of the video and uploaded to other video sharing websites. Check the embedded video

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  • How To Delete Your Skype Call and Chat History

    - by Gopinath
    Just like every other modern application, Skype also records all the communications we exchange using it. It records instant messages, calls, file transfers, SMS, etc. and makes it easy to view using the Conversation tab. If you ever feel like getting rid of these history information, then you need to delete them. Skype provides a single click option to clear all the history from you account, but the feature is buried deep under options menu.Really deep!. To clear history follow the menu Tools –> Options, switch to Privacy Settings tab available on the left side, click on Show advanced options button and finally hit the button Clear history. Ah! You are almost done. Just confirm a popup it displays on screen and your history is vanished from your account. Join us on Facebook to read all our stories right inside your Facebook news feed.

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  • Don’t Like New Google Search Interface? Switch To Old Interface

    - by Gopinath
    Google recently adopted a new user interface layout for it’s search engine. The new layout is very different to classic one, it provides many options on the left side to choose for enhanced search operations. Even though many users like this new interface, there are few who are more comfortable with the classic interface. If you are one among those who wanted to switch back to classic interface, you can access it by using the following http://www.google.com/webhp?hl=all Join us on Facebook to read all our stories right inside your Facebook news feed.

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  • Google Currency Convertor JSON API

    - by Gopinath
    There are many live currency conversion services available on the web and the popular one’s among them are – Google, Yahoo, MSN & XE. Among all these four Google is the developer’s darling and it provides a simple JSON API that can be integrated in your applications.  http://www.google.com/ig/calculator?hl=en&q=1USD=?INR Using the API is very simple and it takes two parameters as input. The first parameter “hl” is the language code in which you want output. The second parameter “q” is the conversion query in the format <number><from currency code>=?<to currency code>. In the URL give above the query requests for conversion of 1 USD in INR. JSON output for the above query would be  similar to {lhs: "1 U.S. dollar",rhs: "54.4602984 Indian rupees",error: "",icc: true} Examples: 100 USD in INR  http://www.google.com/ig/calculator?hl=en&q=100USD=?INR Example 2: 1 GBP in INR http://www.google.com/ig/calculator?hl=en&q=1GBP=?INR Example 3: 1 USD in INR, output the data in French language http://www.google.com/ig/calculator?hl=fr&q=1USD=?INR   This is an undocumented service and expect changes at any time. But as long as it works, you got a programmatic way to convert currencies.

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  • How to enable Start Button in Windows 8?

    - by Gopinath
    Microsoft taken a bold move in removing Start button in Windows 8 operating system and replacing it with Metro styled Start screen. Since the early days of Microsoft Windows, all the PC users are used to Start button and missing it all of sudden in Windows 8 may disappointed many. If you are one among the users who is disappointed with missing Windows 8 button, here is a quick way to enable it back To restore Start menu in Windows 8 all you have to do is to download and install ViStart application. This freeware application magically brings back the missing Start orbit and also when you press Windows Key, it opens up the Start menu instead of switching to Windows 8 Start Screen. Note: While installation the application may ask you to install toolbars and third party application, I suggest you to uncheck them as they may change your search settings and default browser.  They may not be harmful but effects your browsing experience.

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  • Team Foundation Server– Debug symbols(pdb files) generated in Release build? Fix it.

    - by Gopinath
    Yesterday I setup TFS for my .NET playground website to implement continuous integration and deployments. After a successful build I noticed that debug symbols(pdb files) were generated even though TFS is configured to build in Release mode.  After a bit of analysis its turned out to be the behavior of TFS to generate debug symbols (pdb files) until we pass the attribute DebugType = None. Here are the steps to pass DebugType parameter to MSBuild of TFS Go to Team Explorer Select Build Defintion >> Edit Build Definition Switch to Process tab Navigate to Advanced Section and locate MSBuild Arguments Add the following: /p:Configuration=Release /p:DebugType=none

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  • Google Rolls Out Secured Search. It’s Slightly Different From Regular Search

    - by Gopinath
    Google rolled out secured version of it’s search engine at https://google.com (did you notice https instead of http?). This search engine lets everyone to use Google search in a secured way. How is it secured? When you use https://google.com, the data exchanged between your browser and Google servers is encrypted to make sure that no one can sniff it. Is my search history secured from Google? No. The search queries you submit to Google are stored in Google servers. There is no change Google’s search history recording. Any differences between Regular Search and Secured Search Results? Yes. Secured search is slightly different from regular search. When you are accessing Google Secured Search Image search options will not be available on the left side bar. Site may respond slow compared to regular search site as there is a overhead to establish between your browser and the server. Join us on Facebook to read all our stories right inside your Facebook news feed.

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  • SQLAuthority News – Speaking Sessions at TechEd India – 3 Sessions – 1 Panel Discussion

    - by pinaldave
    Microsoft Tech-Ed India 2010 is considered as the major Technology event of the year for various IT professionals and developers. This event will feature a comprehensive forum in order   to learn, connect, explore, and evolve the current technologies we have today. I would recommend this event to you since here you will learn about today’s cutting-edge trends, thereby enhancing your work profile and getting ahead of the rest. But, the most important benefit of all might be the networking opportunity that that you can attain by attending the forum. You can build personal connections with various Microsoft experts and peers that will last even far beyond this event! It also feels good to let you know that I will be speaking at this year’s event! So, here are the sessions that await you in this mega-forum. Session 1: True Lies of SQL Server – SQL Myth Buster Date: April 12, 2010  Time: 11:15pm – 11:45pm In this 30-minute demo session, I am going to briefly demonstrate few SQL Server Myth and their resolution backing up with some demo. This demo session is a must-attend for all developers and administrators who would come to the event. This is going to be a very quick yet  fun session. Session 2: Master Data Services in Microsoft SQL Server 2008 R2 Date: April 12, 2010  Time: 2:30pm-3:30pm SQL Server Master Data Services will ship with SQL Server 2008 R2 and will improve Microsoft’s platform appeal. This session provides an in depth demonstration of MDS features and highlights important usage scenarios. Master Data Services enables consistent decision making by allowing you to create, manage and propagate changes from single master view of your business entities. Also with MDS – Master Data-hub which is the vital component helps ensure reporting consistency across systems and deliver faster more accurate results across the enterprise. We will talk about establishing the basis for a centralized approach to defining, deploying, and managing master data in the enterprise. Session 3: Developing with SQL Server Spatial and Deep Dive into Spatial Indexing Date: April 14, 2010 Time: 5:00pm-6:00pm Microsoft SQL Server 2008 delivers new spatial data types that enable you to consume, use, and extend location-based data through spatial-enabled applications. Attend this session to learn how to use spatial functionality in next version of SQL Server to build and optimize spatial queries. This session outlines the new geography data type to store geodetic spatial data and perform operations on it, use the new geometry data type to store planar spatial data and perform operations on it, take advantage of new spatial indexes for high performance queries, use the new spatial results tab to quickly and easily view spatial query results directly from within Management Studio, extend spatial data capabilities by building or integrating location-enabled applications through support for spatial standards and specifications and much more. Panel Discussion: Harness the power of Web – SEO and Technical Blogging Date: April 12, 2010 Time: 5:00pm-6:00pm Here you will learn lots of tricks and tips about SEO and Technical Blogging from various Industry Technical Blogging Experts. This event will surely be one of the most important Tech conventions of 2010. TechEd is going to be a very busy time for Tech developers and enthusiasts, since every evening there will be a fun session to attend. If you are interested in any of the above topics for every session, I suggest that you visit each of them as you will learn so many things about the topic to be discussed. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: MVP, Pinal Dave, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Author Visit, SQLAuthority News, T SQL, Technology Tagged: TechEd, TechEdIn

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  • What good technology podcasts are out there?

    - by Michael Stum
    Yes, Podcasts, those nice little Audiobooks I can listen to on the way to work. With the current amount of Podcasts, it's like searching a needle in a haystack, except that the haystack happens to be the Internet and is filled with too many of these "Hot new Gadgets" stuff :( Now, even though I am mainly a .NET developer nowadays, maybe anyone knows some good Podcasts from people regarding the whole software lifecycle? Unit Testing, Continous Integration, Documentation, Deployment... So - what are you guys and gals listening to? Please note that the categorizations are somewhat subjective and may not be 100% accurate as many podcasts cover several areas. Categorization is made against what is considered the "main" area. General Software Engineering / Productivity Stack Overflow TekPub (Requires Paid Subscription) SE Radio 43 Folders Perspectives Dr. Dobb's (now a video feed) The Pragmatic Podcast (Inactive) IT Matters Agile Toolkit Podcast The Stack Trace (Inactive) Parleys Techzing The Startup Success Podcast Berkeley CS class lectures FOSS Weekly .NET / Visual Studio / Microsoft Herding Code Hanselminutes .NET Rocks! Deep Fried Bytes Alt.Net Podcast Polymorphic Podcast Sparkling Client (The Silverlight Podcast) dnrTV! Spaghetti Code ASP.NET Podcast Channel 9 Radio TFS PowerScripting Podcast The Thirsty Developer Elegant Code ConnectedShow Crafty Coders Coding QA jQuery yayQuery The official jQuery podcast Java / Groovy The Java Posse Grails Podcast Java Technology Insider Ruby / Rails Railscasts Rails Envy The Ruby on Rails Podcast Rubiverse Web Design / JavaScript / Ajax WebDevRadio Boagworld The Rissington podcast Ajaxian YUI Theater Unix / Linux / Mac / iPhone Mac Developer Network Hacker Public Radio Linux Outlaws Mac OS Ken LugRadio Linux radio show (Inactive) The Linux Action Show! Linux Kernel Mailing List (LKML) Summary Podcast Stanford's iPhone programming class SysAdmin, Security or Infrastructure RunAs Radio Security Now! Crypto-Gram Security Podcast Hak5 VMWare VMTN Windows Weekly PaulDotCom Security The Register - Semi-Coherent Computing FeatherCast General Tech / Business Tekzilla This Week in Tech The Guardian Tech Weekly PCMag Radio Podcast Entrepreneurship Corner Manager Tools Other / Misc. / Podcast Networks IT Conversations Retrobits Podcast No Agenda Netcast Cranky Geeks The Command Line Freelance Radio IBM developerWorks The Register - Open Season Drunk and Retired Technometria Sod This Radio4Nerds Hacker Medley

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  • Is it a wise decision to go from dev to third line/Tier 3 dev support?

    - by dotnetdev
    Hi, I am an experienced, mid-level developer. However, I recently spotted a job for a company which is small but has a lot of emphasis on training(beyond the basic technical training, but also mentoring, leadership training, etc). The role is 3rd line so still very technical. It's in app support so it's post implementation development rather than pure out-and-out development like I do now (or don't, as the senior devs do all of the interesting work). However, and this is the question - is this sort of career move common? Also, wouldn't a tech support role be a big shock to the system because I've never dealt with customers? I therefore think it's a bad move? Working in dev, I am used to the lack of customer contact and it is all filtered through by my manager. But in tech support, contacting customers/rude customers could be scary. I don't mind fixing other people's mistakes (better than me making mistakes!) and doing post-implementation dev for production systems (will give me a lot of discipline), and I do get bored sitting in the same place looking/talking to the same people in suits (I work in a corporate environment). The company puts A LOT of emphasis on training and prospects, which I don't get in the current (big) company I work at. Any advice on how to handle tech support is appreciated! Thanks

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  • Diving into OpenStack Network Architecture - Part 1

    - by Ronen Kofman
    v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} rkofman Normal rkofman 83 3045 2014-05-23T21:11:00Z 2014-05-27T06:58:00Z 3 1883 10739 Oracle Corporation 89 25 12597 12.00 140 Clean Clean false false false false EN-US X-NONE HE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi; mso-bidi-language:AR-SA;} Before we begin OpenStack networking has very powerful capabilities but at the same time it is quite complicated. In this blog series we will review an existing OpenStack setup using the Oracle OpenStack Tech Preview and explain the different network components through use cases and examples. The goal is to show how the different pieces come together and provide a bigger picture view of the network architecture in OpenStack. This can be very helpful to users making their first steps in OpenStack or anyone wishes to understand how networking works in this environment.  We will go through the basics first and build the examples as we go. According to the recent Icehouse user survey and the one before it, Neutron with Open vSwitch plug-in is the most widely used network setup both in production and in POCs (in terms of number of customers) and so in this blog series we will analyze this specific OpenStack networking setup. As we know there are many options to setup OpenStack networking and while Neturon + Open vSwitch is the most popular setup there is no claim that it is either best or the most efficient option. Neutron + Open vSwitch is an example, one which provides a good starting point for anyone interested in understanding OpenStack networking. Even if you are using different kind of network setup such as different Neutron plug-in or even not using Neutron at all this will still be a good starting point to understand the network architecture in OpenStack. The setup we are using for the examples is the one used in the Oracle OpenStack Tech Preview. Installing it is simple and it would be helpful to have it as reference. In this setup we use eth2 on all servers for VM network, all VM traffic will be flowing through this interface.The Oracle OpenStack Tech Preview is using VLANs for L2 isolation to provide tenant and network isolation. The following diagram shows how we have configured our deployment: This first post is a bit long and will focus on some basic concepts in OpenStack networking. The components we will be discussing are Open vSwitch, network namespaces, Linux bridge and veth pairs. Note that this is not meant to be a comprehensive review of these components, it is meant to describe the component as much as needed to understand OpenStack network architecture. All the components described here can be further explored using other resources. Open vSwitch (OVS) In the Oracle OpenStack Tech Preview OVS is used to connect virtual machines to the physical port (in our case eth2) as shown in the deployment diagram. OVS contains bridges and ports, the OVS bridges are different from the Linux bridge (controlled by the brctl command) which are also used in this setup. To get started let’s view the OVS structure, use the following command: # ovs-vsctl show 7ec51567-ab42-49e8-906d-b854309c9edf     Bridge br-int         Port br-int             Interface br-int type: internal         Port "int-br-eth2"             Interface "int-br-eth2"     Bridge "br-eth2"         Port "br-eth2"             Interface "br-eth2" type: internal         Port "eth2"             Interface "eth2"         Port "phy-br-eth2"             Interface "phy-br-eth2" ovs_version: "1.11.0" We see a standard post deployment OVS on a compute node with two bridges and several ports hanging off of each of them. The example above is a compute node without any VMs, we can see that the physical port eth2 is connected to a bridge called “br-eth2”. We also see two ports "int-br-eth2" and "phy-br-eth2" which are actually a veth pair and form virtual wire between the two bridges, veth pairs are discussed later in this post. When a virtual machine is created a port is created on one the br-int bridge and this port is eventually connected to the virtual machine (we will discuss the exact connectivity later in the series). Here is how OVS looks after a VM was launched: # ovs-vsctl show efd98c87-dc62-422d-8f73-a68c2a14e73d     Bridge br-int         Port "int-br-eth2"             Interface "int-br-eth2"         Port br-int             Interface br-int type: internal         Port "qvocb64ea96-9f" tag: 1             Interface "qvocb64ea96-9f"     Bridge "br-eth2"         Port "phy-br-eth2"             Interface "phy-br-eth2"         Port "br-eth2"             Interface "br-eth2" type: internal         Port "eth2"             Interface "eth2" ovs_version: "1.11.0" Bridge "br-int" now has a new port "qvocb64ea96-9f" which connects to the VM and tagged with VLAN 1. Every VM which will be launched will add a port on the “br-int” bridge for every network interface the VM has. Another useful command on OVS is dump-flows for example: # ovs-ofctl dump-flows br-int NXST_FLOW reply (xid=0x4): cookie=0x0, duration=735.544s, table=0, n_packets=70, n_bytes=9976, idle_age=17, priority=3,in_port=1,dl_vlan=1000 actions=mod_vlan_vid:1,NORMAL cookie=0x0, duration=76679.786s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=2,in_port=1 actions=drop cookie=0x0, duration=76681.36s, table=0, n_packets=68, n_bytes=7950, idle_age=17, hard_age=65534, priority=1 actions=NORMAL As we see the port which is connected to the VM has the VLAN tag 1. However the port on the VM network (eth2) will be using tag 1000. OVS is modifying the vlan as the packet flow from the VM to the physical interface. In OpenStack the Open vSwitch agent takes care of programming the flows in Open vSwitch so the users do not have to deal with this at all. If you wish to learn more about how to program the Open vSwitch you can read more about it at http://openvswitch.org looking at the documentation describing the ovs-ofctl command. Network Namespaces (netns) Network namespaces is a very cool Linux feature can be used for many purposes and is heavily used in OpenStack networking. Network namespaces are isolated containers which can hold a network configuration and is not seen from outside of the namespace. A network namespace can be used to encapsulate specific network functionality or provide a network service in isolation as well as simply help to organize a complicated network setup. Using the Oracle OpenStack Tech Preview we are using the latest Unbreakable Enterprise Kernel R3 (UEK3), this kernel provides a complete support for netns. Let's see how namespaces work through couple of examples to control network namespaces we use the ip netns command: Defining a new namespace: # ip netns add my-ns # ip netns list my-ns As mentioned the namespace is an isolated container, we can perform all the normal actions in the namespace context using the exec command for example running the ifconfig command: # ip netns exec my-ns ifconfig -a lo        Link encap:Local Loopback           LOOPBACK  MTU:16436 Metric:1           RX packets:0 errors:0 dropped:0 overruns:0 frame:0           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0           RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b) We can run every command in the namespace context, this is especially useful for debug using tcpdump command, we can ping or ssh or define iptables all within the namespace. Connecting the namespace to the outside world: There are various ways to connect into a namespaces and between namespaces we will focus on how this is done in OpenStack. OpenStack uses a combination of Open vSwitch and network namespaces. OVS defines the interfaces and then we can add those interfaces to namespace. So first let's add a bridge to OVS: # ovs-vsctl add-br my-bridge Now let's add a port on the OVS and make it internal: # ovs-vsctl add-port my-bridge my-port # ovs-vsctl set Interface my-port type=internal And let's connect it into the namespace: # ip link set my-port netns my-ns Looking inside the namespace: # ip netns exec my-ns ifconfig -a lo        Link encap:Local Loopback           LOOPBACK  MTU:65536 Metric:1           RX packets:0 errors:0 dropped:0 overruns:0 frame:0           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0           RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b) my-port   Link encap:Ethernet HWaddr 22:04:45:E2:85:21           BROADCAST  MTU:1500 Metric:1           RX packets:0 errors:0 dropped:0 overruns:0 frame:0           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0           RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b) Now we can add more ports to the OVS bridge and connect it to other namespaces or other device like physical interfaces. Neutron is using network namespaces to implement network services such as DCHP, routing, gateway, firewall, load balance and more. In the next post we will go into this in further details. Linux Bridge and veth pairs Linux bridge is used to connect the port from OVS to the VM. Every port goes from the OVS bridge to a Linux bridge and from there to the VM. The reason for using regular Linux bridges is for security groups’ enforcement. Security groups are implemented using iptables and iptables can only be applied to Linux bridges and not to OVS bridges. Veth pairs are used extensively throughout the network setup in OpenStack and are also a good tool to debug a network problem. Veth pairs are simply a virtual wire and so veths always come in pairs. Typically one side of the veth pair will connect to a bridge and the other side to another bridge or simply left as a usable interface. In this example we will create some veth pairs, connect them to bridges and test connectivity. This example is using regular Linux server and not an OpenStack node: Creating a veth pair, note that we define names for both ends: # ip link add veth0 type veth peer name veth1 # ifconfig -a . . veth0     Link encap:Ethernet HWaddr 5E:2C:E6:03:D0:17           BROADCAST MULTICAST  MTU:1500 Metric:1           RX packets:0 errors:0 dropped:0 overruns:0 frame:0           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000           RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b) veth1     Link encap:Ethernet HWaddr E6:B6:E2:6D:42:B8           BROADCAST MULTICAST  MTU:1500 Metric:1           RX packets:0 errors:0 dropped:0 overruns:0 frame:0           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000           RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b) . . To make the example more meaningful this we will create the following setup: veth0 => veth1 => br-eth3 => eth3 ======> eth2 on another Linux server br-eth3 – a regular Linux bridge which will be connected to veth1 and eth3 eth3 – a physical interface with no IP on it, connected to a private network eth2 – a physical interface on the remote Linux box connected to the private network and configured with the IP of 50.50.50.1 Once we create the setup we will ping 50.50.50.1 (the remote IP) through veth0 to test that the connection is up: # brctl addbr br-eth3 # brctl addif br-eth3 eth3 # brctl addif br-eth3 veth1 # brctl show bridge name     bridge id               STP enabled     interfaces br-eth3         8000.00505682e7f6       no              eth3                                                         veth1 # ifconfig veth0 50.50.50.50 # ping -I veth0 50.50.50.51 PING 50.50.50.51 (50.50.50.51) from 50.50.50.50 veth0: 56(84) bytes of data. 64 bytes from 50.50.50.51: icmp_seq=1 ttl=64 time=0.454 ms 64 bytes from 50.50.50.51: icmp_seq=2 ttl=64 time=0.298 ms When the naming is not as obvious as the previous example and we don't know who are the paired veth interfaces we can use the ethtool command to figure this out. The ethtool command returns an index we can look up using ip link command, for example: # ethtool -S veth1 NIC statistics: peer_ifindex: 12 # ip link . . 12: veth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 Summary That’s all for now, we quickly reviewed OVS, network namespaces, Linux bridges and veth pairs. These components are heavily used in the OpenStack network architecture we are exploring and understanding them well will be very useful when reviewing the different use cases. In the next post we will look at how the OpenStack network is laid out connecting the virtual machines to each other and to the external world. @RonenKofman

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  • Sendmail - Multiple Domains, One Box - Blocking One Or Two Domains

    - by TangoOversway
    I have a number of domains hosted at a web hosting service. They use sendmail to handle incoming email. I have six domains on this service (which we can call aaa.com, bbb.com and so on). Each email account has the same name and one email box. In other words, [email protected], [email protected], [email protected] and all the others go into one box, /var/spool/mail/tango, where my email program on my desktop picks it up. I have done very little work in sendmail. I haven't had to, and I've been warned it's a steep learning curve. But now I'm running into an issue. I was in a business situation where, for years, my email address was on the website for aaa.com. (We won't go into why this was necessary - it wasn't my preference and it's in the past.) Now I'm using [email protected] instead of [email protected]. I was getting about 1,000 or more pieces of spam a day, but SpamAssassin and my own email program caught about 75% of that. (Which still left stuff to delete.) Now, after checking, I see that 90% or more goes to [email protected], the one that was on the web for years. I'd like to deactivate [email protected] and possibly [email protected] and [email protected], but want to keep using [email protected]. Remember, email to tango at any of these domains will go into one email box. I've had people tell me that sendmail can be configured so I can deactivate [email protected] (and other domains) and still use [email protected] (and others, if I want to). In other words, I can configure sendmail to use this account on some domains and not others. One of the people who was teling me this was in tech support at the hosting service. But I wrote to tech support with a work order to do this and now I'm told it can't be done. I can modify config files myself on this account if needed, but I was hoping to just let them do it. (I love delegation -- it means I spend more time doing my stuff.) Is it possible to keep an email account active on one domain and not others with sendmail, when all domains are hosted on the same server? Is there a name for this process or setting? Any information would be helpful - either pointers to instructions so I can do it, or enough info so I can tell tech support, "This is where to look, and it can be done, so please pass my request on to someone who works with sendmail and knows how to do it." Is this something sendmail can do?

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  • DSL connection dropping when starting game

    - by bootoo
    New connection set up last week - have called tech support, signal fine, sending out tech guy tomorrow - however i cant make sense of this using Vista, 2wire connection 6mb ATT conn, wireless, i can browse website, stream video from my PC wirelessly to my xbox, watch Hulu in high res, connection seems fine I load up World of Warcraft, i select Enter World and without fail my 2wire modem 'DSL' light goes red, my internet light goes out, im no longer connected, then after 10 or 15 seconds it works again, but game has kicked me Noticed the same thing on opening or closing Utorrent as well No other phones/devices plugged into the phone jacks in the apartment - why would joining a game cause my DSL to drop? i can only guess it throws a bunch of information to the server when i hit 'enter world' and that causes an issue that shuts my connection down or my router hates me - all help appreciated

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  • Active X Control issue on Terminal Server 2003

    - by Saif Khan
    I have a security camera system which can be viewed remotely via a web browser. It works excellent only with IE 6 and up and requires an ActiveX control "ERViewer.ocx". Some users require to view the cameras via Windows Terminal Server, but when they try to open the link to the DVR they get the prompt ti install the ActiveX and then the browser crashes when they try to install it. I logged in as admin and got the same issue. I called the tech support of the DVR but they have no idea, in other words, the usual useless tech support. Here is what I get in the error log Faulting application iexplore.exe, version 7.0.6000.16735, faulting module ERViewer.ocx, version 1.6.0.8, fault address 0x000064d7. I am sure it could be some kinda permission getting an ocx to run in IE. What else can I tweak?

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