Posts made by normanghenderson
XO Backup Quiesce, VSS - confused
Hi, I'm confused by different versions of documentation for XO, Xenserver etc. and concerned about the recoverability of XO backups of SQL and Exchange server VM's.
- Does an XO backup with advanced option "normal snapshot" use VSS to provide application consistency? I.e. does it use vm-snapshot-with-quiesce or a normal vm-snapshot?
- Some sources say the above only works with an additional installation step but it is unclear what that is, the one I found seems to be obsolete per: https://xen-orchestra.com/blog/xenserver-quiesce-snapshots/ If I do
vssadmin List Providersthe Citrix VSS does NOT appear.
- https://xen-orchestra.com/docs/backups.html#consistent-backup says that quiesced backups (i.e. quiesced snapshots) are deprecated in favor of RAM-enabled backups. Much slower and larger. Is that the only or the best way to ensure apps can be restored without data corruption?
- What IS the recommended snapshot method, to ensure backups taken by XO are 100% safe, notably in the case of complex Windows apps like SQL and Exchange?
RE: XO Backup [NOBAK] for full backups
Here's another case in XCP-ng/Xen, which pre/post hooks for XO backups could be used to solve:
There are many situations in which it would be desirable to shut down a VM before backup and start it up again afterwards, especially these cases in which a storage device or USB device needs to be detached or the backup won't run...
RE: XO Backup [NOBAK] for full backups
Just coming back to this: @olivierlambert
(1) what is the approximate timeframe for VDI.snapshot ?
(2) You said "we have indeed webhooks but for jobs, I wonder it might be trivial to get them for backup" - is that likely to happen soon?
I can't do the code but I can test...
XO Backup [NOBAK] for full backups
Hi, I have a 3.4 TB video repository (as 2 disks due to the 2 TB limit) on a NAS attached to the VM that runs Zoneminder. It isn't necessary nor possible to create backups of that data.
Looking at XO Backup, I find mention that a disk whose name starts [NOBAK] will be ignored in Delta backups. Does that work? Github comments from a year ago make me think that it's still a work in progress.
That's what I need except: it's also necessary to do Full backups periodically and I understand Xen doesn't have a mechanism to ignore a disk when taking a snapshot, therefore nor does XO. Fair enough but, what about in the case of Snapshot Mode Offline?
It should be easy to script the XE CLI to (1) shut down the VM (2) detach the unwanted disks (3) take the snapshot (4) attach the disks (5) start the VM. Would that be a way for XO Backup to ignore disks flagged [NOBAK] on a full backup? Presumably XO Backup is already doing steps 1,3, and 5 for Snapshot Mode Offline. Adding 2 and 4 might not be much work and wouldn't even require UI changes.
Alternatively if there were a way to supply scripts that would add a lot of flexibility to XO Backup: e.g. pre-backup, post-snapshot/pre-export, post-backup.
Thoughts? I'm not much of a programmer but I'm happy to test...
RE: XOA create VM from snapshot makes VDI but VM is lost
I found a solution:
xe template-param-set uuid=8d8bcde8-ebbd-1d0c-7086-58a08602cf02 is-a-template=false
But that shouldn't be necessary... XOA build 20200228 XCP-ng 8.1.0
XOA create VM from snapshot makes VDI but VM is lost
Hi, I just tried the following sequence attempting to get a clean offline backup of a VM:
- shutdown the VM
- took a snapshot
- restarted the VM
- "create a VM from this snapshot" in XOA
The result is that I can see the expected additional 100GB virtual disk on the host under Storage-Local Storage-Disks. But no new VM appeared on the host (or any other host) whether in XOA, xcp-ng center, or the CLI.
xe vdi-list params=all (using the uuid from XOA) shows the disk, with one vbd-uuid. Using that: xe vbd-list uuid=28d567fa-73ed-d945-0f00-b14856340395 uuid ( RO) : 28d567fa-73ed-d945-0f00-b14856340395 vm-uuid ( RO): 8d8bcde8-ebbd-1d0c-7086-58a08602cf02 vm-name-label ( RO): cem01vs4-cold-20200501-vm vdi-uuid ( RO): 0a3281e0-e709-4d68-93a5-562ea0720924 empty ( RO): false device ( RO): xvda
vm-name-label is indeed the name I gave the vm when creating it from the snapshot.
and with params=all the only thing that looks odd is "allowed operations (SRO) :" (blank)
However: xe vm-list knows no such VM, and xe vm-export can't find it by UUID or by name.
The whole objective of the exercise is to export the newly-created VM to offline storage (preferably compressed)...
Any ideas what happened or how to fix it?