[Pacemaker] Pacemaker remote nodes, naming, and attributes

[David Vossel]

----- Original Message -----
> From: "David Vossel" <dvossel at redhat.com>
> To: "The Pacemaker cluster resource manager" <pacemaker at oss.clusterlabs.org>
> Sent: Thursday, June 20, 2013 1:35:44 PM
> Subject: Re: [Pacemaker] Pacemaker remote nodes, naming, and attributes
> 
> ----- Original Message -----
> > From: "David Vossel" <dvossel at redhat.com>
> > To: "The Pacemaker cluster resource manager"
> > <pacemaker at oss.clusterlabs.org>
> > Sent: Wednesday, June 19, 2013 4:47:58 PM
> > Subject: Re: [Pacemaker] Pacemaker remote nodes, naming, and attributes
> > 
> > ----- Original Message -----
> > > From: "Lindsay Todd" <rltodd.ml1 at gmail.com>
> > > To: "The Pacemaker cluster resource manager"
> > > <Pacemaker at oss.clusterlabs.org>
> > > Sent: Wednesday, June 19, 2013 4:11:58 PM
> > > Subject: [Pacemaker] Pacemaker remote nodes, naming, and attributes
> > > 
> > > I built a set of rpms for pacemaker 1.1.0-rc4 and updated my test cluster
> > > (hopefully won't be a "test" cluster forever), as well as my VMs running
> > > pacemaker-remote. The OS everywhere is Scientific Linux 6.4. I am wanting
> > > to
> > > set some attributes on remote nodes, which I can use to control where
> > > services run.
> > > 
> > > The first deviation I note from the documentation is the naming of the
> > > remote
> > > nodes. I see:
> > > 
> > > 
> > > 
> > > 
> > > Last updated: Wed Jun 19 16:50:39 2013
> > > Last change: Wed Jun 19 16:19:53 2013 via cibadmin on cvmh04
> > > Stack: cman
> > > Current DC: cvmh02 - partition with quorum
> > > Version: 1.1.10rc4-1.el6.ccni-d19719c
> > > 8 Nodes configured, unknown expected votes
> > > 49 Resources configured.
> > > 
> > > 
> > > Online: [ cvmh01 cvmh02 cvmh03 cvmh04 db02:vm-db02 ldap01:vm-ldap01
> > > ldap02:vm-ldap02 swbuildsl6:vm-swbuildsl6 ]
> > > 
> > > Full list of resources:
> > > 
> > > and so forth. The "remote-node" names are simply the hostname, so the
> > > vm-db02
> > > VirtualDomain resource has a remote-node name of db02. The "Pacemaker
> > > Remote" manual suggests this should be displayed as "db02", not
> > > "db02:vm-db02", although I can see how the latter format would be useful.
> > 
> > Yep, this got changed since the documentation was published.  We wanted
> > people to be able to recognize which remote-node went with which resource
> > easily.
> > 
> > > 
> > > So now let's set an attribute on this remote node. What name do I use?
> > > How
> > > about:
> > > 
> > > 
> > > 
> > > 
> > > # crm_attribute --node "db02:vm-db02" \
> > > --name "service_postgresql" \
> > > --update "true"
> > > Could not map name=db02:vm-db02 to a UUID
> > > Please choose from one of the matches above and suppy the 'id' with
> > > --attr-id
> > > 
> > > Perhaps not the most informative output, but obviously it fails. Let's
> > > try
> > > the unqualified name:
> > > 
> > > 
> > > 
> > > 
> > > # crm_attribute --node "db02" \
> > > --name "service_postgresql" \
> > > --update "true"
> > > Remote-nodes do not maintain permanent attributes,
> > > 'service_postgresql=true'
> > > will be removed after db02 reboots.
> > > Error setting service_postgresql=true (section=status, set=status-db02):
> > > No
> > > such device or address
> > > Error performing operation: No such device or address
> 
> I just tested this and ran into the same errors you did.  Turns out this
> happens when the remote-node's status section is empty.  If you start a
> resource on the node and then set the attribute it will work... obviously
> this is a bug. I'm working on a fix.

This should help with the attributes bit.

https://github.com/ClusterLabs/pacemaker/commit/26d34a9171bddae67c56ebd8c2513ea8fa770204

-- Vossel