On Fri, Jan 20, 2012 at 01:09:56PM +1100, Andrew Beekhof wrote: > On Thu, Jan 19, 2012 at 12:15 AM, Dejan Muhamedagic <deja...@fastmail.fm> > wrote: > > On Wed, Jan 18, 2012 at 06:58:20PM +1100, Andrew Beekhof wrote: > >> On Wed, Jan 18, 2012 at 6:00 AM, Dejan Muhamedagic <deja...@fastmail.fm> > >> wrote: > >> > Hello, > >> > > >> > On Tue, Jan 03, 2012 at 05:19:14PM +1100, Andrew Beekhof wrote: > >> >> Does anyone have an opinion on the following schema and example? > >> >> I'm not a huge fan of the index field, but nor am I of making it > >> >> sensitive to order (like groups). > >> > > >> > What is wrong with order in XML elements? It seems like a very > >> > clear way to express order to me. > >> > >> Because we end up with the same update issues as for groups. > > > > OK. > > > > [...] > > > >> > Is there a possibility to express > >> > fencing nodes simultaneously? > >> > >> No. Its regular boolean shortcut semantics. > > > > As digimer mentioned, it is one common use case, i.e. for hosts > > with multiple power supplies. So far, we recommended lights-out > > devices for such hardware configurations and if those are > > monitored and more or less reliable such a setup should be fine. > > It would still be good to have a way to express it if some day > > somebody actually implements it. I guess that the schema can be > > easily extended by adding a "simultaneous" attribute to the > > "fencing-rule" element. > > So in the example below, you'd want the ability to not just trigger > the 'disk' and 'network' devices, but the ability to trigger them at > the same time?
Right. > >> >> Most people will /NOT/ need to add this section to their configuration. > >> >> > >> >> -- Andrew > >> >> > >> >> <fencing-topology> > >> >> <!-- pcmk-0 requires the devices named disk + network to complete --> > >> >> <fencing-rule id="f-p0" node="pcmk-0"> > >> >> <device id-ref="disk"/> > >> >> <device id-ref="network"/> > >> >> </fencing-rule> > >> >> > >> >> <!-- pcmk-1 needs either the poison-pill or power device to complete > >> >> successfully --> > >> >> <fencing-rule id="f-p1.1" node="pcmk-1" index="1" > >> >> device="poison-pill"/> > >> >> <fencing-rule id="f-p1.2" node="pcmk-1" index="2" device="power"> > >> >> > >> >> <!-- pcmk-1 needs either the disk and network devices to complete > >> >> successfully OR the device named power --> > >> >> <fencing-rule id="f-p2.1" node="pcmk-2" index="1"> > >> >> <device id-ref="disk"/> > >> >> <device id-ref="network"/> > >> >> </fencing-rule> > >> >> <fencing-rule id="f-p2.2" node="pcmk-2" index="2" device="power"/> > >> >> > >> >> </fencing-topology> > >> >> > >> >> Conforming to: > >> >> > >> >> <define name="element-stonith"> > >> >> <element name="fencing-topology"> > >> >> <zeroOrMore> > >> >> <ref name="element-fencing"/> > >> >> </zeroOrMore> > >> >> </element> > >> >> </define> > >> >> > >> >> <define name="element-fencing"> > >> >> <element name="fencing-rule"> > >> >> <attribute name="id"><data type="ID"/></attribute> > >> >> <attribute name="node"><text/></attribute> > >> >> <attribute name="index"><text/></attribute> > >> >> <choice> > >> >> <attribute name="device"><text/></attribute> > >> >> <zeroOrMore> > >> >> <element name="device"> > >> >> <attribute name="id-ref"><data type="IDREF"/></attribute> > >> >> </element> > >> >> </zeroOrMore> > >> >> </choice> > >> >> </element> > >> >> </define> > >> > > >> > I'd rather use "stonith-resource" than "device", because what is > >> > referenced is a stonith resource (one device may be used in more > >> > than one stonith resource). > >> > >> Can you rephrase that? I don't follow. Are you talking about a group > >> of fencing devices? > > > > No, just about naming. The element/attribute name "device" > > doesn't seem right to me, because it references a stonith > > resource. One (physical) device may be used by more than one > > stonith resource. Even though "device" certainly sounds nicer, > > it isn't precise. > > Oh, I see what you mean. I'll see what I can come up with. OK. Cheers, Dejan > > What I'm worried about is that it may be > > confusing (and we have enough confusion with stonith). > > (Or did I completely misunderstand the meaning of "device"?) > > > > Thanks, > > > > Dejan > > > >> > Or "stonith-rsc" if you're in the > >> > shortcuts mood. Or perhaps even "agent". > >> > > >> > "fencing-rule" for whatever reason doesn't sound just right, but > >> > I have no alternative suggestion. > >> > >> Agreed. > >> > >> > > >> > IMO, as I already said earlier, index is superfluous. > >> > > >> > It could also be helpful to consider multiple nodes in a single > >> > element. > >> > > >> > Otherwise, looks fine to me. > >> > > >> > Thanks, > >> > > >> > Dejan > >> > > >> >> </grammar> > >> >> > >> >> _______________________________________________ > >> >> Pacemaker mailing list: Pacemaker@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://bugs.clusterlabs.org > >> > > >> > _______________________________________________ > >> > Pacemaker mailing list: Pacemaker@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://bugs.clusterlabs.org > >> > >> _______________________________________________ > >> Pacemaker mailing list: Pacemaker@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://bugs.clusterlabs.org > > > > _______________________________________________ > > Pacemaker mailing list: Pacemaker@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://bugs.clusterlabs.org > > _______________________________________________ > Pacemaker mailing list: Pacemaker@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://bugs.clusterlabs.org _______________________________________________ Pacemaker mailing list: Pacemaker@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://bugs.clusterlabs.org
