Hi,
I have noticed recently that when a client(W2k8 VM) is busy (eg. heavy CPU load), NetBackup fails to create successful snapshot(error 156 - quiescing failed). Snapshots can be taken in vCenter with no problems, Here are the things i noticed:
1. Snapshots triggered in vCenter always work fine regardless of the settings or VM load (quiescing of VM's memory and file system can be enabled or disabled and it just works fine in any combination).
2. Disabling application quiescing in VMtools following below instructions fixes the problem with error 156 in NetBackup (not good solution for systems running MS databases!):
- open C:\ProgramData\VMware\VMware Tools\Tools.conf in the text editor. If the file does not exist, create it.
- Add these lines to the file:
[vmbackup]
vss.disableAppQuiescing = true
3. Job progress bar in vCenter moves forward siginificantly faster when snapshot is initiated in NetBackup.
I have been previously advised following things by different support groups:
- it is a problem with VMware - not true as snapshots started in vCenter work fine regardless of options set.
- it is a problem with VSS - again, if true snapshots should fail regardless of application initiating the job.
Considering the above observations i went into a conclusion that there are different settings (possibly quiescing timeout) for snapshots triggered from vCenter and NetBackup.
Can anyone please shine a little bit more light on the policies and mechanisms NetBackup uses to trigger snapshot jobs in vCenter?
Many thanks,
M.