Question

I am intermittently facing the ErrorCode:SubStatus with Windows Azure and the App Fabric cache in my ASP.NET application. This brings my whole web application to a standstill until I reset it making Azure no longer viable.

I am only storing very small strings in Session state and only have a very small number of users. I can’t imagine that I could be over any of the usage quotas (at http://msdn.microsoft.com/en-us/library/gg602420.aspx#C_BKMK_FAQ8)

I would like to find out which quota if any I am exceeding and why. How can I find out if and why I am being throttled, or if there is any other issue that might be causing this.

Is there any way to find the Cache Size (I know this is in the Management Portal but it always reports ir over 95% lower than my 128MB limit), Transactions Per Hour, Bandwidth MB Per Hour and Concurrent Connections?

Stack trace:

Application_Error: ErrorCode:SubStatus:There is a temporary failure. Please retry later. (One or more specified cache servers are unavailable, which could be caused by busy network or servers. For on-premises cache clusters, also verify the following conditions. Ensure that security permission has been granted for this client account, and check that the AppFabric Caching Service is allowed through the firewall on all cache hosts. Also the MaxBufferSize on the server must be greater than or equal to the serialized object size sent from the client.)Stack Trace: at Microsoft.ApplicationServer.Caching.DataCache.ThrowException(ResponseBody respBody)
at Microsoft.ApplicationServer.Caching.DataCache.ExecuteAPI(RequestBody reqMsg, IMonitoringListener listener)
at Microsoft.ApplicationServer.Caching.DataCache.InternalPut(String key, Object value, DataCacheItemVersion oldVersion, TimeSpan timeout, DataCacheTag[] tags, String region, IMonitoringListener listener)
at Microsoft.ApplicationServer.Caching.DataCache.<>c_DisplayClass25.b_24()
at Microsoft.ApplicationServer.Caching.MonitoringListenerFactory.EmptyListener.Microsoft.ApplicationServer.Caching.IMonitoringListener.Listen[TResult](Func1 innerDelegate)
at Microsoft.ApplicationServer.Caching.DataCache.Put(String key, Object value, TimeSpan timeout)
at Microsoft.Web.DistributedCache.DataCacheWrapper.Put(String key, Object value, TimeSpan timeout)
at Microsoft.Web.DistributedCache.DataCacheForwarderBase.<>c__DisplayClass10.<Put>b__f()
at Microsoft.Web.DistributedCache.DataCacheForwarderBase.<>c__DisplayClass2e1.b__2d()
at Microsoft.Web.DistributedCache.DataCacheRetryWrapper.PerformCacheOperation(Action action)
at Microsoft.Web.DistributedCache.DataCacheForwarderBase.PerformCacheOperation[TResult](Func`1 func)
at Microsoft.Web.DistributedCache.DataCacheForwarderBase.Put(String key, Object value, TimeSpan timeout)
at Microsoft.Web.DistributedCache.BlobBasedSessionStoreProvider.SetAndReleaseItemExclusive(HttpContextBase context, String id, SessionStateStoreData item, Object lockId, Boolean newItem)
at Microsoft.Web.DistributedCache.DistributedCacheSessionStateStoreProvider.SetAndReleaseItemExclusive(HttpContext context, String id, SessionStateStoreData item, Object lockId, Boolean newItem)
at System.Web.SessionState.SessionStateModule.OnReleaseState(Object source, EventArgs eventArgs)
at System.Web.SessionState.SessionStateModule.OnEndRequest(Object source, EventArgs eventArgs)
at System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) on page

Answer 1

Take a look at the Windows Azure Service Dashboard. Go to the bottom, and under Status History, select AppFabric Caching. Look for periods of service degradation or interruption on the days you saw this error (including today), for your given data center.

Hope that helps…