[PVE-User] Proxmox and DRBD

[Klaus Darilion]

Hi!

Reading the archives I learnt that Proxmox removed DRBD as the
consequence of license issues (which were reverted). As far as is know
this was about DRBD9 and older Proxmox releases had support for DRBD8.

Checking the Proxmox sources (storage modules) it seems that there is
still some code for DRBD left, but apperently not used.

IMO it is a real pitty that DRBD is not supported anymore. There are
several use case where DRBD is a perfect and cost efficient solution
avoiding additional external storages. Debian 9 comes with DRBD8 out of
the - so why not use it (without needed any additonal software from Linbit)?

Is there any technical reason why DRBD(8) is not supported anymore?

Is it possible to activate and use the leftover DRBD code in Proxmox?

If not, I think the simple "manual" solution would be a DRBD-backed LVM
storage in active-active mode. Any experiences with such a setup (except
that it is not nice to have a single DRBD ressource for all VMs instead
of one DRBD ressource per virtual disk)?

Thanks
Klaus

[Alwin Antreich]

Hello Klaus,

Hi!
Reading the archives I learnt that Proxmox removed DRBD as the consequence
of license issues (which were reverted). As far as is know this was about
DRBD9 and older Proxmox releases had support for DRBD8.

Linbit itself took on them to support PVE, they have a repository and
manual for that.

Checking the Proxmox sources (storage modules) it seems that there is still
some code for DRBD left, but apperently not used.
IMO it is a real pitty that DRBD is not supported anymore. There are several
use case where DRBD is a perfect and cost efficient solution avoiding
additional external storages. Debian 9 comes with DRBD8 out of the - so why
not use it (without needed any additonal software from Linbit)?

Check out the pvesr for storage replication.
https://pve.proxmox.com/pve-docs/chapter-pvesr.html

Is there any technical reason why DRBD(8) is not supported anymore?

The storage plugin is, AFAIR only for DRBD9.
https://docs.linbit.com/docs/users-guide-9.0/#ch-proxmox

Is it possible to activate and use the leftover DRBD code in Proxmox?
If not, I think the simple "manual" solution would be a DRBD-backed LVM
storage in active-active mode. Any experiences with such a setup (except
that it is not nice to have a single DRBD ressource for all VMs instead of
one DRBD ressource per virtual disk)?

Try pvesr, as mentioned above, it uses ZFS and snapshots to replicate
volumes, less hassle then with DRBD, IMHO. Or give Ceph a go, integrated
into PVE.

--
Cheers,
Alwin

[Klaus Darilion]

Post by Alwin Antreich

Post by Klaus Darilion
Is it possible to activate and use the leftover DRBD code in Proxmox?
If not, I think the simple "manual" solution would be a DRBD-backed LVM
storage in active-active mode. Any experiences with such a setup (except
that it is not nice to have a single DRBD ressource for all VMs instead of
one DRBD ressource per virtual disk)?

Try pvesr, as mentioned above, it uses ZFS and snapshots to replicate
volumes, less hassle then with DRBD, IMHO. Or give Ceph a go, integrated
into PVE.

We currently use ZFS replication, but it does not support live
migration. Further, I think it does not support HA - does it?

Klaus

[Yannis Milios]

Both drbd8 and drbd9 can be configured in pve without issues. The former,
can be configured in pairs of two pve nodes, where for the latter, three
pve nodes is the minimum.IIRC drbd8 kmod is included by default in the pve
kernel, so you will only need to install drbd-utils to get started.
For drbd9, follow the instructions as described in Linbit's
documentation.In my opinion enabling HA in just 2 pve nodes, with drbd8 in
dual primary mode, is just too dangerous.As a minimum, proper (hardware)
fencing must be configured in both drbd and pve to avoid data corruption.

[Alwin Antreich]

Post by Klaus Darilion

Post by Alwin Antreich

Post by Klaus Darilion
Is it possible to activate and use the leftover DRBD code in Proxmox?
If not, I think the simple "manual" solution would be a DRBD-backed LVM
storage in active-active mode. Any experiences with such a setup (except
that it is not nice to have a single DRBD ressource for all VMs instead

of

Post by Alwin Antreich

Post by Klaus Darilion
one DRBD ressource per virtual disk)?

Try pvesr, as mentioned above, it uses ZFS and snapshots to replicate
volumes, less hassle then with DRBD, IMHO. Or give Ceph a go, integrated
into PVE.

We currently use ZFS replication, but it does not support live
migration. Further, I think it does not support HA - does it?

The storage replication doesn't work with live migration yet but HA is
possible, see first section of the docs.

Post by Klaus Darilion
https://pve.proxmox.com/pve-docs/chapter-pvesr.html

--
Cheers,
Alwin

[Dietmar Maurer]

Post by Klaus Darilion
IMO it is a real pitty that DRBD is not supported anymore.

You can get DRBD support from Linbit.