XFS for LXC container

[Reinis Rozitis]

Hello,
is there a workaround (or a tweak for mount options for the backup process) for a LXC container to work correctly with XFS mount point?

Currently for a newly created CT I can simply attach an ext4 volume from the GUI and then convert it to xfs volume but it breaks backup as XFS doesn't support the 'noload' mount option:

[ 2129.625945] XFS (dm-28): unknown mount option [noload].

Nov 2 19:54:53 box pvedaemon[13563]: ERROR: Backup of VM 113 failed - command 'mount -o ro,noload /dev/dm-28 /mnt/vzsnap0//data' failed: exit code 32
Nov 2 19:54:53 box pvedaemon[13563]: INFO: Backup job finished with errors

 

[dietmar]

Please open a bug report at bugzilla.proxmox.com

 

[dietmar]

Besides, why do you want xfs instead of ext4?

 

[Reinis Rozitis]

Please open a bug report at bugzilla.proxmox.com

https://bugzilla.proxmox.com/show_bug.cgi?id=1194
(not sure if the component is right - does it apply to vzdump or pve-container)

Besides, why do you want xfs instead of ext4?

I have somewhat better experience (performance, crash recovery etc) using it as filesystem for MySQL.

 

[grin]

Besides, why do you want xfs instead of ext4?

Better preformance, more reliability. But this is a religious debate really. My counter-question is: why not?

(And I am searching the forum about how to create an xfs formatted lxc container from the start.... so far no luck.)

 

[moxfan]

Currently for a newly created CT I can simply attach an ext4 volume from the GUI and then convert it to xfs volume

How do you attach an ext4 volume to the CT from the GUI?

 

[Reinis Rozitis]

How do you attach an ext4 volume to the CT from the GUI?

ext4 is the default filesystem for lxc but to attach an new one you just go to particular container in the GUI then choose Resources and there is an Add / Mount point option.

 

[moxfan]

ext4 is the default filesystem for lxc but to attach an new one you just go to particular container in the GUI then choose Resources and there is an Add / Mount point option.

I still don't understand how you are able to use XFS for the container's raw file when LXC containers seem to have been hard-wired to use ext4? Do you mind briefly running through it?

 

[Reinis Rozitis]

I still don't understand how you are able to use XFS for the container's raw file when LXC containers seem to have been hard-wired to use ext4? Do you mind briefly running through it?

Rather than raw files I'm using thin provisioned LVS volumes (probably would be the same with zfs backed zvols) so when the container is stopped you can convert (and mount if needed) the volumes on the host.

p.s. There is no (at least I don't know) straight forward ext4->xfs conversion without data loss. So while it's simple with empty volumes/mount points, for the rootfs you have to mount the volume, then backup the data, format and then sync it back. Afterwards you can just quickly clone new LXC cotainers with vzdump and pct restore to keep the setup .. just the backup function won't work from the GUI.

 

[moxfan]

There is no (at least I don't know) straight forward ext4->xfs conversion without data loss. So while it's simple with empty volumes/mount points, for the rootfs you have to mount the volume, then backup the data, format and then sync it back. Afterwards you can just quickly clone new LXC cotainers with vzdump and pct restore to keep the setup .. just the backup function won't work from the GUI.

What do you recommend to use to back up the rootfs? Rsync? Tar?