In the binary log extract below we see “VSS_E_FLUSH_WRITES_TIMEOUT”. This error is coming from the shadow copy services on the client that is being backed up and it would appear that the snapshot is timing out while creating the snapshot.
Error 2015/03/05 10:45:24 65 Data Plugin MCRR01DMP Error creating volume snapshot(s): VSS_E_FLUSH_WRITES_TIMEOUT
Error 2015/03/05 10:45:24 65 Data Plugin MCRR01DMP Failed to create VSS snapshot
While creating snapshot on the client, the snapshot creation times out due to system resourse problem.
Below are configuration changes we can make to reduce the likelihood of this problem happening.
1/ One reason for this could be that the system was busy at the time so rescheduling the backup to a time when the disk is not busy would help.
2/ issue this command from the command line on the client that we are backing up “vssadmin list writers”
If we see a filed writer we will need to reboot the client to clear this
3/ issue this command from the command line on the client that we are backing up “vssadmin List ShadowStorage”
if we see that the designated snapshot area is full we can increase using command like the one below:
vssadmin resize shadowstorage /For=D: /On=D: /MaxSize=20GB
4/ issue this command from the command line on the client that we are backing up “vssadmin List shadows”
If we have lots of shadow set on the disks we are trying to backup we can delete these see Microsoft article below for this: