[Pacemaker] master/slave problems

[Dejan Muhamedagic]

Hi,

On Wed, Mar 16, 2011 at 08:47:18AM +0100, Uwe Grawert wrote:
> Hi,
> 
> Am 16.03.11 02:27, schrieb Sam Pinar:
> > I've setup a two node cluster for testing using the "Clusters from Scratch -
> > Apache, DRBD and GFS2" guide. I've set it up and fail over works like a
> > charm, but I want one of the nodes to be a master; and fail back resources
> > to the master when it comes back up. At the moment, the resource stays at
> > the failed back node. configs:
> > 
> > 
> > node ULTPLN30.DMZ
> > node ULTPLN31.DMZ \
> >         attributes standby="off"
> > primitive ClusterIP ocf:heartbeat:IPaddr2 \
> >         params ip="10.110.4.123" cidr_netmask="32" \
> >         op monitor interval="30s"
> > property $id="cib-bootstrap-options" \
> >         dc-version="1.1.5-1.1.el5-01e86afaaa6d4a8c4836f68df80ababd6ca3902f"
> > \
> >         cluster-infrastructure="openais" \
> >         expected-quorum-votes="2" \
> >         stonith-enabled="false" \
> >         no-quorum-policy="ignore"
> 
> if you want to do that, you have to give your resource a stickyness to
> the node you define as master. Say your master is ULTPLN30.DMZ, then you
> have to define a location constraint, which sticks your resource to that
> node.
> 
> The following command assignes a stickyness with weight of 10 to your

It is called "node preference". Resource stickiness is a score
which is added for the node that _currently_ runs the resource.

> first node. As long as this rule is not outvoted by another rule, your
> resource will stick to the defined node.
> 
> crm configure location loc_ip_stick_to_master ClusterIP 10: ULTPLN30.DMZ

Since this is a ms resource, the role has to be specified:

location loc_ip_stick_to_master ClusterIP rule $role=Master 10: #uname eq ULTPLN30.DMZ

> Have a look at location constraints: crm configure help location

Thanks,

Dejan

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