Exception cleaning tokens is a recurring error that appears.

[tbrettallen]

• [x] I read and understood how to enable logging

Question / Issue

Is this a bug in Identity Server or an issue with our configuration/setup?

Relevant parts of the log file

25 Oct 2017 09:09:31.285
 Exception cleaning tokens
 Application F1.Auth
 ClientTimestamp 2017-10-25T09:09:32.4949195-05:00
 MachineName RD0003FF661D73
 ProcessId 60116
 SourceContext IdentityServer3.EntityFramework.TokenCleanup
 ThreadId 519
System.Data.Entity.Infrastructure.DbUpdateConcurrencyException: Store update, insert, or delete statement affected an unexpected number of rows (0). Entities may have been modified or deleted since entities were loaded. See http://go.microsoft.com/fwlink/?LinkId=472540 for information on understanding and handling optimistic concurrency exceptions. ---> System.Data.Entity.Core.OptimisticConcurrencyException: Store update, insert, or delete statement affected an unexpected number of rows (0). Entities may have been modified or deleted since entities were loaded. See http://go.microsoft.com/fwlink/?LinkId=472540 for information on understanding and handling optimistic concurrency exceptions.
   at System.Data.Entity.Core.Mapping.Update.Internal.UpdateTranslator.ValidateRowsAffected(Int64 rowsAffected, UpdateCommand source)
   at System.Data.Entity.Core.Mapping.Update.Internal.UpdateTranslator.<UpdateAsync>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Data.Entity.Core.Objects.ObjectContext.<ExecuteInTransactionAsync>d__3d`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Data.Entity.Core.Objects.ObjectContext.<SaveChangesToStoreAsync>d__39.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.<ExecuteAsyncImplementation>d__9`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Data.Entity.Core.Objects.ObjectContext.<SaveChangesInternalAsync>d__31.MoveNext()
   --- End of inner exception stack trace ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at IdentityServer3.EntityFramework.TokenCleanup.<ClearTokens>d__4.MoveNext() in c:\git\identity\server3\EntityFramework\Source\Core.EntityFramework\TokenCleanup.cs:line 110

[brockallen]

Sounds like you have 2 of them running at the same time. This is more of an EF issue anyway. If you need the behavior changed anytime soon, I'd suggest forking the EF repo and making that change in there.