Proxmox 4.4 and DRBD which Version is recommended?

[hape]

Hello all,

we use a two-node cluster and want to setup DRBD to mirror the image of the VMs to both nodes. I'm a little bit confused on which version (8 or 9) should i use, and how can i install it?

Does anybody have any experience on setup, and can make a recommendation?

Regards

Hans-Peter

 

[Mitch Maris]

following

 

[wolfgang]

Hi,

on PVE 4 you can only use DRBD9 or you have to compile your own kernel.

PVE will come with DRBD8 modules so you can choose what you will do.

The most user in this forum report that DRBD 8 better for 2 nodes setup.

But keep in mind that there is no HA with 2 nodes.

 

[Mitch Maris]

Morgan @wolfgang

I believe the OP has some confusion about which is the best to use currently.

On the enterprise repo, we still have access to DRBD files.

Spoiler: apt search drbd

root@pve1:~# apt search drbd
Sorting... Done
Full Text Search... Done
drbd-doc/stable 8.4~20140825-1 all
  RAID 1 over TCP/IP for Linux (user documentation)

drbd-utils/stable 8.9.8-1 amd64
  RAID 1 over TCP/IP for Linux (user utilities)

drbd-utils-dbg/stable 8.9.2~rc1-2+deb8u1 amd64
  RAID 1 over TCP/IP for Linux (user utilities' debug symbols)

drbd8-utils/stable 2:8.9.8-1 amd64
  transitional dummy package

drbdlinks/stable 1.22-1 all
  Manages symlinks into a shared DRBD partition

drbdmanage/stable 0.97.3-1 amd64
  Distributed configuration management for DRBD

nagios-plugins-contrib/stable 14.20141104 amd64
  Plugins for nagios compatible monitoring systems

If we want to make a 2 node cluster (with third witness proxmox server) using DRBD as the storage, should we use the packages in the enterprise (or free, would need to check) or stick to the linbit repo?

Thanks

Mitch

 

[wolfgang]

This are old packages and we do not delete old packages.

On PVE 4.4 you have to use the linbit repos if you like to use DRBD.

 

[Mitch Maris]

think that makes it crystal clear, thanks @wolfgang

 

[hape]

Hello all,

i'm continuing confused about the possible setup.

Isn't it possible to make a 2 nodes setup with really only 2 members?

I only want a filesystem mirroring such as raid-1 (on 2 nodes), and a ha-cluster setup with only one failover-host as backup.

 

[Mitch Maris]

@hape Proxmox 4 uses corosync for cluster management (HA) which requires 3 nodes to make quorum. Proxmox 3 you could make a 2 node cluster. Proxmox 5 you'll again have the ability to make 2 node (with a third whitness device maybe a raspberry pi) cluster again but it's still in development and specifics are not yet documented on the wiki

DRDB 8 could have a 2 node cluster, I am unsure about v9 as my attempts to set it up in a virtual cluster was unsuccessful and time has not allowed further investigation/completion.

 

[wolfgang]

For HA you need always min 3 participants.
Some use tiebreaker like switches,etc.

Two node can never now the true state and will produce splitbrain in time.
Consider the following network is lost witch of the 2 nodes are down?
Both node don't see the other node. Conclusion the other node is down I take the job. Result splitbrain.