failed to quiesce

[glassin]

    I have the latest update to esxi 6.  Using the latest dell vsm 4.7.  My jobs run but almost every vm gets this error message when the job completes with errors

failed to create VM snapshot for "server"  An error occured while saving the snapshot.  Failed to quiesce virtual machine.

I've spent alot of time searching but i'm not fully understanding whats going wrong so the links i've found aren't helping me much.  I do know the windows servers will get vss errors at that time, and at least one application will have an issue (this is where i started to notice issue)  Today I restored one of these datastores with multiple vm's that claimed to have failed with this error.  I restored and powered on a test server with a file created before the job ran and it was there fine.  So...

is this error valid?

can i trust all of my backup / replications?

worth while to disable quiesce on the server with application that is crashing during this time?   if so how?

did i pick the correct forum for this question?

thanks for the help.

[virtualg_uk]

Hello & Welcome to VMTN!

VM quiescing can be tested by running the following powercli command.

I would suggest running this against the same VM and seeing if this completes or not. If it does complete, then there is possibly an issue with your backup solution / backup agent installed on the VM if applicable.

Now to your questions:

Is the error valid

Yes, probably. if you have applications such as SQL, Exchange on the VM then you will need to quiesce those as part of the backup job to ensure that they are in a consistent state while the backup copies the files. This would ensure that the backups for those applications are recoverable.

Can I trust backups / replication

Possibly, if you do not have those kinds of applications that require quiescing on any of your VMs, then there might not be a need to worry about this error.

Disable quiesce

Again, probably okay if your applications do not require this to happen upon getting backed up. If they do, some restores might work because the apps were already in a state ready for backup, but you run the risk of some restores not working.

Correct forum

Sure, it's a possible vSphere issue that you are experiencing.

More information from official KB:

• Quiesce: If the flag is 1 or true, and the virtual machine is powered on when the snapshot is taken, VMware Tools is used to quiesce the file system in the virtual machine. Quiescing a file system is a process of bringing the on-disk data of a physical or virtual computer into a state suitable for backups. This process might include such operations as flushing dirty buffers from the operating system's in-memory cache to disk, or other higher-level application-specific tasks.
  
  Note: Quiescing indicates pausing or altering the state of running processes on a computer, particularly those that might modify information stored on disk during a backup, to guarantee a consistent and usable backup. Quiescing is not necessary for memory snapshots; it is used primarily for backups.
• Source: VMware Knowledge Base

[MartyA2]

I have similar issue,

where is the powercli command that you speak of?

Thanks for the post,

[virtualg_uk]

Apologies, I completely forgot to paste that in!

You will want to do something like this:

new-snapshot -vm $VM -name "snapshot name" -quiesce:$true

See for more details the new-snapshot cmdlet here: VMware PowerCLI Cmdlets Reference

[perromateric]

Have you read this KB VMware Knowledge Base ?

[perromateric]

i have gotten this problem with Veam Backup and I used this solutions on my windows VM (from the kb)

Disable VSS application quiescing using VMware Tools:

1. Open the C:\ProgramData\VMware\VMware Tools\Tools.conf file using a text editor.
2. Add these entries to the file:
   
   [vmbackup]
   vss.disableAppQuiescing = true
   
   
3. Save and close the file.
4. Restart the VMware Tools Service.
   1. Click Start > Run, type services.msc, and click OK.
   2. Right-click the VMware Tools Service and click Restart.

[glassin]

Just wanted to update, as of right now the latest vmware tools has resolved the issue.  And by latest i mean monday / tuesday new tools were available and since upgrading my vsm schedules aren't failing snapshots.   Fingers crossed for the future.

EDIT:  latest tools and still failing again this week.  Will update if / when i have more.

EDIT: This was due to two competing backup processes.  Dell VSM snapshots of the entire servers, and rapid recovery doing file backups, although staggered one or the other would not let go of vss writers.  I simply stopped using VSM in favor of using the equal logic itself for hourly SAN replication.  Have not had a problem since.