Application Aware Processing for Linux and Windows database servers - Tmanok

[Tmanok]

Hi Proxmox Team!

Not sure if I asked a similar question recently, couldn't find it if I did but I know that this has been troubling me a lot lately. After working with Veeam long ago and recently supporting an organization that relies on it heavily, I was reminded that it offers Application Aware Processing for guests. What this means is that it can backup VMs running databases without any disk loss. Perhaps I have not read up on it enough, but does Proxmox backup services communicate with the guest in any way to perform such data protection functions?? I don't think so based on my searches...

E.g. Microsoft SQL Server or RDBMS or PostGRESQL or MariaDB, which each have tools to write all live transactions before the filesystem is snapshotted during backups using tools such as Veeam.

If not, will there be plans to implement this? What about configurations for pre-backup scripts? If not, then the solution will be to configure those DBs running in PVE environments to manually back themselves up using best practices. The trouble is that some DB Admins are not very aware of the ideal backup strategies (e.g. more than one copy) and most HV admins don't seem to be DB Admins haha...

Thanks! Also, if there isn't already, perhaps the Wiki should have a nice big attractive warning that screams at PVE admins to backup DBs manually and regularly check their scheduling as part of best practices hahaha...

Tmanok

 

[dcsapak]

Hi,

for VMs backed up on PVE, we initiate a guest-agent filesystem 'freeze' and 'thaw' (if the guest agent is activated & installed).
the qemu-guest-agent has a 'fsfreeze hook' where you can put your custom commands

there is an example for linux + mysql flush in the qemu repo: https://github.com/qemu/qemu/blob/m...t-agent/fsfreeze-hook.d/mysql-flush.sh.sample

 

[Tmanok]

Hi,

for VMs backed up on PVE, we initiate a guest-agent filesystem 'freeze' and 'thaw' (if the guest agent is activated & installed).
the qemu-guest-agent has a 'fsfreeze hook' where you can put your custom commands

there is an example for linux + mysql flush in the qemu repo: https://github.com/qemu/qemu/blob/m...t-agent/fsfreeze-hook.d/mysql-flush.sh.sample

Hi Dominik!

Perfect, thank you, that's the type of pre-backup script functionality I was looking for. Is there anything like this for Windows guests?
Thank you sir!

Tmanok

 

[dcsapak]

mhmm i don't know if the windows guest agent has something similar to those hooks, but it's using VSS on freeze/thaw, maybe one can hook into that?

 

[Tmanok]

After doing quite a bit of Googling and asking the more Windows-centric administrators in town I haven't found a similar featureset. The answer I've come up with is simply schedule MS SQL to make a backup a few minutes (or an hour if necessary) before the PVE/PBS backup commences. That way there is always a stable written copy on disk.

The concern is that it adds additional administrative steps, and if a new staff member comes in during say my absence, they may restore the VM and not realize that they also need to restore the DB to ensure perfect consistency... The solution to that might be to shut down the VM during backup. If there are multiple MS SQL servers that replicate to each other then it's less of an issue for the running DB, just becomes a bigger issue for whatever service or application is relying on that DB. Anyway many consequential headaches soon follow with rebooting a Windows system too, I really wish there was a good way to tie it into PBS directly for that reason.

Thanks again Dominik!


Tmanok