[ClusterLabs] Antw: Re: Best-practices for changing networks settings in a cluster?

[Ulrich Windl]

>>> Ken Gaillot <kgaillot at redhat.com> schrieb am 06.11.2018 um 00:12 in Nachricht
<1541459570.5061.11.camel at redhat.com>:
> On Mon, 2018-11-05 at 16:14 -0600, Ryan Thomas wrote:
>> I have a two node cluster.  I restart the network after making
>> changes to the network settings.  But, as soon as I restart the
>> network I see that corosync/pacemaker are killed - causing resources
>> to failover to the other node.  It looks like this is due to https://
>> github.com/corosync/corosync/issues/348, this issue points that that
>> corosync cannot handle downing an network interface with ifdown.  I'd
>> like to avoid this, but I'd still like to be able to change the
>> network settings. What is the best-practice for changing network
>> settings on a cluster?  
>> 
>> The best workaround I can think of is to kill pacemaker on each
>> process, make the network changes, and then restart pacemaker. 
>> However, this seems pretty ugly and error-prone.  Is there  away to
>> "pause" pacemaker for the whole cluster?  
>> 
>> Thanks in advance for your advice.
>> Ryan
> 
> Hi,
> 
> Yes, maintenance mode is exactly for this purpose. You can set the
> maintenance-mode cluster property to true, stop pacemaker and corosync,
> update the network, start corosync and pacemaker, then set maintenance-
> mode back to false.

Hi!

Does this still hold when running DLM, cLVM and/or OCFS2? In my experience the nodes were fences still...

Regards,
Ulrich

> -- 
> Ken Gaillot <kgaillot at redhat.com>
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