[ClusterLabs] Can I add a pacemaker v2 node to a v2 cluster ?

[Ken Gaillot]

On Fri, 2024-03-01 at 15:41 +0000, Morgan Cox wrote:
> Hi - i have a fair few rhel7 pacemaker clusters (running on pacemaker
> v1)   I want to migrate to rhel8 (which uses pacemaker v2) - due to
> using shared/cluster ip it would be a pain  and involve downtime to
> take down cluster ip on rhel7 cluster then setup on rhel8.
> 
> Can I add a pacemaker v2 node to a pacemaker v1 one  (in order to
> migrate easily..)

No, the Corosync versions are incompatible. The closest you could do
would be to set up booth between the Pacemaker 1 and 2 clusters, then
grant the ticket to the new cluster. That's effectively the same as
manually disabling the IP on the old cluster and enabling it on the new
one, but a little more automated (which is more helpful the more
resources you have to move).

> 
> i.e i have these versions 
> 
> rhel7 : pacemaker-1.1.23-1.el7_9.1.x86_64
> rhel8: pacemaker-2.1.5-8.el8.x86_64
> 
> For the purposes of migrating to rhel8 - could i add a rhel8
> (pacemaker v2) node to an existing rhel7 (pacemaker v1.x) cluster 
> 
> If it matters here is the 'supporting' versions of both (using #
> pacemakerd --features )
> 
> rhel7: Supporting v3.0.14:  generated-manpages agent-manpages ncurses
> libqb-logging libqb-ipc systemd nagios  corosync-native atomic-attrd
> acls
> 
> rhel8 :  Supporting v3.16.2: agent-manpages cibsecrets compat-2.0
> corosync-ge-2 default-concurrent-fencing default-sbd-sync generated-
> manpages monotonic nagios ncurses remote systemd
> 
> If this is not possible I will have to think of another solution.
> 
> Thanks 
> 
-- 
Ken Gaillot <kgaillot at redhat.com>