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Autoscaling Windows Azure applications

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  • User profile image

    What I see in management protal doesnt actually make sense. When scale up or down is happening, it seems that all instances are updating. I expect that the working instances keep working when scale up is happening.

  • User profile image

    @Meisam: When you go into the configuration and change the # of instances, all of the currently running instances will appear to update because they are all receiving an event indicating that the configuration has changed. If you handle that event, make sure to set Cancel to false to indicate that you do *not* want the role to restart.;k(TargetFrameworkMoniker-%22.NETFRAMEWORK%2cVERSION%3dV4.0%22);k(DevLang-CSHARP)&rd=true">;k(TargetFrameworkMoniker-%22.NETFRAMEWORK%2cVERSION%3dV4.0%22);k(DevLang-CSHARP)&rd=true


  • User profile image

    Thanks for the video. It is helpful. A few questions:

    1) What is alias attribute? Video has name attribute but I believe it is replaced by alias? Does it connect rules?

    <service ...>
    <role roleName="ScalingHelloWorld" wadStorageAccountName="wadStorageAccount" alias="1">
    </role> </roles> </service> </services>

    <storageAccount connectionString="UseDevelopmentStorage=true" alias="1"> </storageAccount>

    2) What about certificates? Do we have to add any additional certificates to make this work other than two that we add on Management portal and under hosted service?

  • User profile image

    From this example and Tailspin on MSDN, I get feeling that the autoscaling host should be different from the target. Is this the case? Can I have a worker role host which references WASABi library and applies scaling rules on itself to autoscale itself?

  • User profile image


    Sorry, I didn't get notifications about your questions and only saw them today.

    1) Yes, in the final version this attribute is called "alias".

    2) You need to make the management ceriticate available to the role hosting Wasabi. This means deploying it through the Windows Azure portal and adding it to the list of certificates for the role. Then you also have to specify that certificate's thumbprint for the subscription element in the services store.

    3) You can have Wasabi autoscale itself (the block is prepared to deal with multiple instances of the autoscaler - we are using an execution lease), but that's not necessarily something that you would probably want to do. The technical reason is that it's better for an autoscaler to be running continuously in an instance. If you modify your app and decide to redeploy, the autoscaler will need to be interrupted and redeployed as well. Thus, it's better to run in its own role - an extra small worker or web role would do.



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