[DRBD-user] Managing a 3-node DRBD 9 resource in pacemker

[Lars Ellenberg]

On Sun, Feb 11, 2018 at 07:08:49PM -0500, Digimer wrote:
> Hi all,
> 
>   I was trying to manage DRBD in pacemaker for a test cluster I built.
> It's a 3-node cluster; Node 1 & 2 are in pacemaker and are protocol C
> with proper fencing. The third node is a DR node, protocol A.
> 
>   At first, I just added DRBD as a systemd service (quick and dirty, I
> know it's not good long term). When I had the DR node's drbd service
> running, everything was fine. When I down'ed it though, pacemaker said
> it timed out starting drbd (I assume because both nodes were still
> waiting for the DR node to connect).
> 
>   So I decided to try to switch to ocf:linbut:drbd, but I don't know how
> to set it up such that it doesn't care about the DR node's state
> (specially because the DR is not part of the pacemaker cluster).
> 
>   Is it possible with the current RA to setup such that it only monitors
> the two nodes in pacemaker and ignores the state of the DR node?

I'm sure you'll let us know ;-)

If pacemaker does not know about that DR node,
the DRBD RA does not know much about it either,
and master-max 1, clone-max 2 "just like it used to be".

The peer-disk state of the DR node as seen by drbdsetup
may have some influence on the master-score calculations.
That's a feature, not a bug ;-)
(I think)

-- 
: Lars Ellenberg
: LINBIT | Keeping the Digital World Running
: DRBD -- Heartbeat -- Corosync -- Pacemaker

DRBD® and LINBIT® are registered trademarks of LINBIT
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