Am having some occassional problems where the backup of a system is having issues with the system state backup. (Vss snapshot fails) Filesystem agent (windows server 2012 and 2016). The initial file scan fails. Sometimes it takes several attempts to work. Very occassionally the backup fails, but often it recovers. It is seeming to occur on a random number of systems, and varies from night to night. On a couple of occassions I've gone into a system, and restarted the various services as a "vssadmin list writers" will show several that are in a failed state.
I opened a ticked back in January and the response was that this is an MS problem, and I'd have to talk to them about it.
I get that, but surely someone has some CV knowledge on what sort of things to look for, and some ideas and/or experience in resolving this sort of problem.
I recently update from SP16 to SP18 hoping that might help, but it did not.
Regarding numbers. Am backing up 200+ servers/systems a night, and the problem only occurs on a handful on a particular day ( less than 5).
The Windows event logs report VSS failure with "system reserved" volume.