Sitecore 9 Processing Server - Exception when executing agent pathAnalyzer/mapRebuildStatusCheckerAgent

Question

I am getting below error in Processing role. Our version is sitecore 9.0.2. Anyone faced similar issues?

Exception: System.AggregateException
Message: One or more errors occurred.
Source: mscorlib
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at Sitecore.PathAnalyzer.Processing.Agents.MapRebuildStatusCheckerAgent.d__8.MoveNext()
   at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
   at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
   at Sitecore.PathAnalyzer.Processing.Agents.MapRebuildStatusCheckerAgent.Execute()
   at Sitecore.Analytics.Core.BackgroundService.Run()

Nested Exception

Exception: System.AggregateException
Message: One or more errors occurred.
Source: mscorlib
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at Sitecore.PathAnalyzer.Processing.Agents.MapRebuildStatusCheckerAgent.d__9.MoveNext()

Nested Exception

Exception: Sitecore.Analytics.Core.Data.EntityDoesNotExistException
Message: Routine caused exception: Processing_GetTaskById.
Source: Sitecore.Analytics.Sql
   at Sitecore.Analytics.Processing.SqlTaskDataProvider.d__51.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Sitecore.Analytics.Processing.SqlTaskDataProvider.d__41.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Sitecore.Analytics.Processing.Internals.TaskHub.d__15.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Sitecore.Analytics.Processing.TaskManager.d__8.MoveNext()

Nested Exception

Exception: System.Data.SqlClient.SqlException
Message: A processing task with the specified unique identifier does not exist.
Source: .Net SqlClient Data Provider
   at System.Data.SqlClient.SqlCommand.c.b__180_0(Task`1 result)
   at System.Threading.Tasks.ContinuationResultTaskFromResultTask`2.InnerInvoke()
   at System.Threading.Tasks.Task.Execute()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Sitecore.Xdb.Sql.Common.Extensions.DbCommandExtensions.c__DisplayClass1_0.b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Sitecore.Xdb.Sql.Common.Extensions.DbCommandExtensions.d__1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Sitecore.Xdb.Sql.Common.Extensions.SqlCommandExtensions.d__1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Sitecore.Xdb.Sql.Common.Extensions.SqlCommandExtensions.d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Sitecore.Analytics.Processing.SqlTaskDataProvider.d__51.MoveNext()

Answer 1

I experienced the same issue during upgrading from Sitecore 8.1 Update-1 to Sitecore 9.0 Update-2.

The reason here is quite simple:

I missed executing a step from the Upgrade Guide.

The chapter 10.3.4 Upgrade Path Analyzer in the Upgrade Guide states that you need to redeploy the Path Analyzer Maps after updating your Sitecore instance to version 9.0 or later:

In Sitecore XP 9.0 or later, the deployed Path Analyzer maps are stored in a different format. You must, therefore, redeploy the Path Analyzer maps.

To redeploy the Path Analyzer maps:

1. In SQL Server Management Studio, in the Reporting database, to remove all the data from the TreeDefinitions table, execute the following command: Delete from TreeDefinitions.
2. In Sitecore, open the admin page of the Path Analyzer –/sitecore/admin/pathanalyzer.aspx.
3. In the Maps Manager section, click Deploy all maps that are not deployed.

Make sure to back up the reporting database before executing the mentioned steps.

Answer 2

I just went through this on a Sitecore 9.1 install. Our issue was post a report DB rebuild. When I looked at the TaskId column, there was two different GUIDs spread out between all the tasks. The fix for me was to set all the TaskId values to an empty GUID with the SQL below.

This came from Sitecore support.

Declare @EmptyGuid uniqueidentifier
Set @EmptyGuid = '00000000-0000-0000-0000-000000000000'

UPDATE [dbo].[TreeDefinitions] SET TaskId = @EmptyGuid 

Answer 3

Below response from Sitecore helped to Solved the issue. 1. In the Reporting database, to remove all the data from the TreeDefinitions table, execute the following command: Delete from TreeDefinitions. 2. In Sitecore, open the admin page of the Path Analyzer - /sitecore/admin/pathanalyzer.aspx. 3. In the Maps Manager section, click Deploy all maps that are not deployed. 4. In the Historic Map Rebuild section, click Rebuild.