Hi everyone!

I have a huge exchange 2013 environment with about 10k mailboxes. The CAS feature is segregated. Some of the servers (with the same hardware configuration) have started to keep messages in submission queue and it just let it go after an IISRESET. I noticed before the procedure that the CPU was in the top of use mainly by the IIS process. 

I don't have anti-virus installed on it. But we have a lot of transport rules. About 200. 

I didn't find out nothing special on EV. Just some times back-pressure. But why after the IISRESET the queue starts flowing again?

All releases are CU7.

Regards

Hi,

When run IISRESET, restarting IIS unloads all Web applications from memory, restarts the IIS service and refreshes the cache.
For your question, can you confirm the problem process which cause high CPU usage and message queue in Submission?
Please check the relevant event log and run Test-ServiceHealth to check the health of Exchange server.

Thanks

Hi Allen,

That's the question! I don't know what has been causing the message queue in submission. 

Only thing that I can see is a high CPU usage and always the Edge Transport is the most responsible for consumption of CPU.

The service health is ok also.

I think that it could be a kind of bug in exchange. The EV didn't show anything that could helps.

I am looking for someone who already passed for this situation.

Regards,