[ClusterLabs] [External] : Re: Fence Agent tests

[Robert Hayden]

> -----Original Message-----
> From: Users <users-bounces at clusterlabs.org> On Behalf Of Valentin Vidic
> via Users
> Sent: Sunday, November 6, 2022 5:20 PM
> To: users at clusterlabs.org
> Cc: Valentin Vidić <vvidic at valentin-vidic.from.hr>
> Subject: Re: [ClusterLabs] [External] : Re: Fence Agent tests
> 
> On Sun, Nov 06, 2022 at 09:08:19PM +0000, Robert Hayden wrote:
> > When SBD_PACEMAKER was set to "yes", the lack of network connectivity
> to the node
> > would be seen and acted upon by the remote nodes (evicts and takes
> > over ownership of the resources).  But the impacted node would just
> > sit logging IO errors.  Pacemaker would keep updating the /dev/watchdog
> > device so SBD would not self evict.   Once I re-enabled the network, then
> the
> 
> Interesting, not sure if this is the expected behaviour based on:
> 
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> Does SBD log "Majority of devices lost - surviving on pacemaker" or
> some other messages related to Pacemaker?

Yes.

> 
> Also what is the status of Pacemaker when the network is down? Does it
> report no quorum or something else?
> 

Pacemaker on the failing node shows quorum even though it has lost 
communication to the Quorum Device and to the other node in the cluster.
The non-failing node of the cluster can see the Quorum Device system and 
thus correctly determines to fence the failing node and take over its 
resources.

Only after I run firewall-cmd --panic-off, will the failing node start to log
messages about loss of TOTEM and getting a new consensus with the 
now visible members.

I think all of that explains the lack of self-fencing when the sbd setting of
SBD_PACEMAKER=yes is used.

> --
> Valentin
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