I'm having a problem with a Hyper-V guest that is running Exchange 2013 CU5. I will say I have had issues with this VM since installing CU5.
Note: I am doing a backup from within the VM guest, not from the host.
The scheduled backup takes a long time to complete, an entire weekend to backup 150GB to an ISCSI disk. In addition the CPU time is very high (58%) while this is happening. Attempting to open the backup manager window consistently makes the CPU time hit 99%. When this happens Outlook clients will fail. When backup manager opens it will continually say "Reading data; please wait..." If the backup manager happened to already been open, the backup job will say "Volume 1 0% of 4 volumes."
The processes taking up the CPU time are Microsoft Volume Shadow Copy Service (24%), Microsoft Block level backup service (62%) and virtual disk service (12%). Memory use always hovers around 65%. If I attempt to kill the processes with task manager, there is no change. If I use the kill executable it will say the process is not running. I cannot stop the corresponding service either. I cannot stop the backup. I cannot query vss writer status. I cannot restart the ISCSI service (device in use.) Restarting the NAS that contains the ISCSI target does nothing. The only recourse is to restart the server.
If I restart the server and start a backup fairly soon after, the backup completes normally, in about an hour. During a normal backup CPU usage is at about 30%. The Microsoft Volume Shadow Copy Service runs at 0% CPU time as well as the virtual disk service. The Microsoft Block Level Backup Engine runs at 10% CPU time. The scheduled backup is set to start at 9:30pm. I have also tried changing backup times. If I restart the server at 4 am and do not run a manual backup, the scheduled backup performs poorly.
After some digging I find these errors:
Log Name: ApplicationSource: MSExchangeRepl
Date: 10/14/2014 9:30:41 PM
Event ID: 2112
Task Category: Exchange VSS Writer
Level: Error
Keywords: Classic
User: N/A
Description:
The Microsoft Exchange Replication service VSS Writer instance 7a465f3f-25ba-45b2-952a-870a6ddc2f2b failed with error code 80070020 when preparing for a backup of database 'Mailbox Database 2123847568'.
Log Name: Application
Source: VSS
Date: 10/14/2014 9:30:41 PM
Event ID: 8229
Task Category: None
Level: Warning
Keywords: Classic
User: N/A
Description:
A VSS writer has rejected an event with error 0x00000000, The operation completed successfully.
. Changes that the writer made to the writer components while handling the event will not be available to the requester. Check the event log for related events from the application hosting the VSS writer.
Operation:
PrepareForBackup event
Context:
Execution Context: Writer
Writer Class Id: {7e47b561-971a-46e6-96b9-696eeaa53b2a}
Writer Name: MSMQ Writer (MSMQ)
Writer Instance Name: MSMQ Writer (MSMQ)
Writer Instance ID: {b8ae6140-7fcb-427d-9493-e070221f752f}
Command Line: C:\Windows\system32\mqsvc.exe
Process ID: 1676
Log Name: Application
Source: MSExchangeRepl
Date: 10/14/2014 9:30:41 PM
Event ID: 2024
Task Category: Exchange VSS Writer
Level: Error
Keywords: Classic
User: N/A
Description:
The Microsoft Exchange Replication service VSS Writer (Instance 7a465f3f-25ba-45b2-952a-870a6ddc2f2b) failed with error 80070020 when preparing for a backup.
As you can see the errors happen almost immediately after the backup starts.
In addition the following VSSwriters show a last error "timed out"
Microsoft Exchange Writer
Com+ RegDB Writer
Shadow Copy Optimization Writer
Registry Writer
I will add also the following issues I have been experiencing ever since installing CU5:
1 Version buckets threshold easy reached. Had to modify threshold and set limits on email size. Sometimes still happens.
2 After a restart of the server, the server may have no, or limited connection to the network. It may or may not have an exclamation point on the network icon. If there is no exclamation point, it can ping other network resources, but inbound requests
and pings, will fail. The event log shows that the network should be available while booting, but it's not since it cannot communicate with active directory. The fix for this is to disable/enable the network adapter and then all is well.
I really need some help figuring this out. Again, never had an issue with this server prior to Exchange 2013 CU5 being installed.