On Sat, Mar 19, 2011 at 11:55 AM, Holger Teutsch <holger.teut...@web.de> wrote: > Hi Dejan, > > On Fri, 2011-03-18 at 14:24 +0100, Dejan Muhamedagic wrote: >> Hi, >> >> On Fri, Mar 18, 2011 at 12:21:40PM +0100, Holger Teutsch wrote: >> > Hi, >> > I would like to submit 2 patches of an initial implementation for >> > discussion. > .. >> > To recall: >> > >> > crm_resource --move resource >> > creates a "standby" rule that moves the resource off the currently >> > active node >> > >> > while >> > >> > crm_resource --move resource --node newnode >> > creates a "prefer" rule that moves the resource to the new node. >> > >> > When dealing with clones and masters the behavior was random as the code >> > only considers the node where the first instance of the clone was >> > started. >> > >> > The new code behaves consistently for the master role of an m/s >> > resource. The options "--master" and "rsc:master" are somewhat redundant >> > as a "slave" move is not supported. Currently it's more an >> > acknowledgement of the user. >> > >> > On the other hand it is desirable (and was requested several times on >> > the ML) to stop a single resource instance of a clone or master on a >> > specific node. >> > >> > Should that be implemented by something like >> > >> > "crm_resource --move-off --resource myresource --node devel2" ? >> > >> > or should >> > >> > crm_resource refuse to work on clones >> > >> > and/or should moving the master role be the default for m/s resources >> > and the "--master" option discarded ? >> >> I think that we also need to consider the case when clone-max is >> less than the number of nodes. If I understood correctly what you >> were saying. So, all of move slave and move master and move clone >> should be possible. >> > > I think the following use cases cover what can be done with such kind of > interface: > > crm_resource --moveoff --resource myresource --node mynode > -> all resource variants: check whether active on mynode, then create > standby constraint > > crm_resource --move --resource myresource > -> primitive/group: convert to --moveoff --node `current_node` > -> clone/master: refused > > crm_resource --move --resource myresource --node mynode > -> primitive/group: create prefer constraint > -> clone/master: refused
Not sure this needs to be refused. Other than that the proposal looks sane. My first thought was to make --move behave like --move-off if the resource is a clone or /ms, but since the semantics are the exact opposite, that might introduce introduce more problems than it solves. Does the original crm_resource patch implement this? > > crm_resource --move --resource myresource --master --node mynode > -> master: create prefer constraint for master role > -> others: refused > > They should work (witch foreseeable outcome!) regardless of the setting of > clone-max. > > Regards > Holger > > >> Cheers, >> >> Dejan >> >> > Regards >> > Holger >> > > > > _______________________________________________ > 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://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker > _______________________________________________ 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://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker