On Tue, Nov 08, 2016 at 12:54:10PM +0100, Klaus Wenninger wrote: > On 11/08/2016 11:40 AM, Kostiantyn Ponomarenko wrote: > > Hi, > > > > I need a way to do a manual fail-back on demand. > > To be clear, I don't want it to be ON/OFF; I want it to be more like > > "one shot". > > So far I found that the most reasonable way to do it - is to set > > "resource stickiness" to a different value, and then set it back to > > what it was. > > To do that I created a simple script with two lines: > > > > crm configure rsc_defaults resource-stickiness=50 > > crm configure rsc_defaults resource-stickiness=150 > > > > There are no timeouts before setting the original value back. > > If I call this script, I get what I want - Pacemaker moves resources > > to their preferred locations, and "resource stickiness" is set back to > > its original value. > > > > Despite it works, I still have few concerns about this approach. > > Will I get the same behavior under a big load with delays on systems > > in cluster (which is truly possible and a normal case in my environment)? > > How Pacemaker treats fast change of this parameter? > > I am worried that if "resource stickiness" is set back to its original > > value to fast, then no fail-back will happen. Is it possible, or I > > shouldn't worry about it? > > AFAIK pengine is interrupted when calculating a more complicated transition > and if the situation has changed a transition that is just being executed > is aborted if the input from pengine changed. > So I would definitely worry! > What you could do is to issue 'crm_simulate -Ls' in between and grep for > an empty transition. > There might be more elegant ways but that should be safe.
crmsh has an option (-w) to wait for the PE to settle after committing configuration changes. Thanks, Dejan > > > Thank you, > > Kostia > > > > > > _______________________________________________ > > Users mailing list: [email protected] > > http://clusterlabs.org/mailman/listinfo/users > > > > Project Home: http://www.clusterlabs.org > > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf > > Bugs: http://bugs.clusterlabs.org > > > > _______________________________________________ > Users mailing list: [email protected] > http://clusterlabs.org/mailman/listinfo/users > > Project Home: http://www.clusterlabs.org > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf > Bugs: http://bugs.clusterlabs.org _______________________________________________ Users mailing list: [email protected] http://clusterlabs.org/mailman/listinfo/users Project Home: http://www.clusterlabs.org Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf Bugs: http://bugs.clusterlabs.org
