[Pacemaker] Failing back a multi-state resource eg. DRBD

[Dejan Muhamedagic]

Hi,

On Fri, Mar 04, 2011 at 09:12:46AM -0500, David McCurley wrote:
> Are you wanting to move all the resources back or just that one resource?
> 
> I'm still learning, but one simple way I move all resources back from nodeb to nodea is like this:
> 
> # on nodeb
> sudo crm node standby
> # now services migrate to nodea
> # still on nodeb
> sudo crm node online
> 
> This may be a naive way to do it but it works for now :)

Yes, that would work. Though that would also make all other
resources move from the standby node.

> There is also a "crm resource migrate" to migrate individual resources.  For that, see here:

resource migrate has no option to move ms resources, i.e. to make
another node the master.

What would work right now is to create a temporary location
constraint:

location tmp1 ms-drbd0 \
        rule $id="tmp1-rule" $role="Master" inf: #uname eq nodea

Then, once the drbd got promoted on nodea, just remove the
constraint:

crm configure delete tmp1

Obviously, we'd need to make some improvements here. "resource
migrate" uses crm_resource to insert the location constraint,
perhaps we should update it to also accept the role parameter.

Can you please make an enhancement bugzilla report so that this
doesn't get lost.

Thanks,

Dejan

> http://www.clusterlabs.org/doc/crm_cli.html
> 
> 
> ----- Original Message -----
> > From: "Dominic Malolepszy" <dmalolepszy at optusnet.com.au>
> > To: pacemaker at oss.clusterlabs.org
> > Sent: Thursday, March 3, 2011 12:18:51 AM
> > Subject: [Pacemaker] Failing back a multi-state resource eg. DRBD
> > Hi,
> > 
> > I'm trying to simulate various scenarios and what to do to correct the
> > problem. I have a DRBD cluster as defined below; if the primary fails
> > (ie power cycled drbd01.test), the secondary (drbd02.test) takes over
> > successfully, so DRBD:master now runs on drbd02.test. When node
> > drbd01.test comes back up, DRBD:master remains on drbd02.st (ie due to
> > resource stickness); and drbd01.test simply becomes DRBD:Slave; this
> > is what I want.
> > 
> > Now what command/s would I need to run to move the master back to
> > drbd01.test, and make drbd02.test the new slave? The name of the
> > multi-state resource is ms-drbd0, below is the config I am currently
> > running.
> > 
> > 
> > node drbd01.test \
> > attributes standby="off"
> > node drbd02.test \
> > attributes standby="off"
> > primitive drbd0 ocf:linbit:drbd \
> > params drbd_resource="drbd0" \
> > op monitor interval="60s" \
> > op start interval="0" timeout="240s" \
> > op promote interval="0" timeout="90s" start-delay="3s" \
> > op demote interval="0" timeout="90s" start-delay="3s" \
> > op notify interval="0" timeout="90s" \
> > op stop interval="0" timeout="100s" \
> > op monitor interval="10s" role="Master" timeout="20s" start-delay="5s"
> > \
> > op monitor interval="20s" role="Slave" timeout="20s" start-delay="5s"
> > primitive fs0 ocf:heartbeat:Filesystem \
> > params directory="/var/lib/pgsql/9.0/data" device="/dev/drbd0"
> > fstype="ext3" \
> > op start interval="0" timeout="60s" start-delay="1s" \
> > op stop interval="0"
> > primitive ip ocf:heartbeat:IPaddr \
> > params ip="192.168.1.50" cidr_netmask="24" \
> > op monitor interval="10s"
> > primitive pgsql0 ocf:heartbeat:pgsql \
> > params pgctl="/usr/pgsql-9.0/bin/pg_ctl" \
> > params psql="/usr/pgsql-9.0/bin/psql" \
> > params pgdata="/var/lib/pgsql/9.0/data" \
> > op monitor interval="30s" timeout="30s" \
> > op start interval="0" timeout="120s" start_delay="1s" \
> > op stop interval="0" timeout="120s"
> > primitive ping_gateway ocf:pacemaker:ping \
> > params host_list="192.168.1.1" multiplier="1000" \
> > op monitor interval="10s" timeout="60s" \
> > op start interval="0" timeout="60s" \
> > op stop interval="0" timeout="20s"
> > ms ms-drbd0 drbd0 \
> > meta master-max="1" master-node-max="1" notify="true"
> > clone-node-max="1" clone-max="2"
> > clone connectivity_check ping_gateway \
> > meta globally-unique="false"
> > location master-connected-node ms-drbd0 \
> > rule $id="master-connected-node-rule" $role="master" -inf: not_defined
> > pingd or pingd lte 0
> > location primary_location ip 50: drbd01.test
> > colocation fs0-with-drbd0 inf: fs0 ms-drbd0:Master
> > colocation ip-with-pgsql0 inf: ip pgsql0
> > colocation pgsql0-with-fs0 inf: pgsql0 fs0
> > order fs0-after-drbd0 inf: ms-drbd0:promote fs0:start
> > order ip-after-pgsql0 inf: pgsql0 ip
> > order pgsql0-after-fs0 inf: fs0:start pgsql0
> > property $id="cib-bootstrap-options" \
> > cluster-infrastructure="openais" \
> > expected-quorum-votes="2" \
> > stonith-enabled="false" \
> > no-quorum-policy="ignore" \
> > dc-version="1.0.10-da7075976b5ff0bee71074385f8fd02f296ec8a3"
> > rsc_defaults $id="rsc-options" \
> > resource-stickiness="100"
> > 
> > 
> > Cheers,
> > Dominic.
> > _______________________________________________
> > Pacemaker mailing list: Pacemaker at oss.clusterlabs.org
> > http://oss.clusterlabs.org/mailman/listinfo/pacemaker
> > 
> > Project Home: http://www.clusterlabs.org
> > Getting started:
> > http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> > Bugs:
> > http://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker
> 
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> 
> Project Home: http://www.clusterlabs.org
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