[DRBD-user] .drbdctrl and resource roles

[Julien Escario]

Le 09/11/2018 à 11:20, Roland Kammerer a écrit :
> On Thu, Nov 08, 2018 at 09:58:28PM +0200, Daniel Hertanu wrote:
>> I would like to understand why, on server2, .drbdctrl role is secondary and
>> res1 role is primary, while on server3 .drbdctrl role is primary and res1
>> role is secondary.
> 
> Why not? A resource is Primary on that host that "uses" it. Auto-promote
> with DRBD9 and an open(), or set to Primary.
> 
>> I can switch res1 primary role between server2 and server3 without problems
>> but I can't do anything about .drbdctrl. Trying to change the role to
>> secondary on server3 doesn't return any error but it's just not happening.
> 
> a) don't touch the control-volume. Drbdmanage, and only drbdmanage is
> responsible to switch it Primary on a node. You do not do that manually,
> DM selects one. You can stop all nodes, manually switch it to Primary on
> your favorite host and then start all cluster nodes. Then you
> "preselected" a leader node.

May I add that's it's already a strange state as AFAIK when no
management task is executed BOTH .drbdctrl should be in secondary state.
It only becomes primary when drbdmanage change 'something' (move disk,
reconfigure, etc ...).

> b) forget everything in a), remove drbdmanage, and install LINSTOR.

You'll save you some time.

Best regards,
Julien Escario