Le 20/03/2013 04:11, Quentin Smith a écrit :
Is there any way to get Pacemaker to delay resource transitions until at
least one full polling cycle has happened, so that in the event of an
outage of the ping target, resources stay put where they are running?
there is the "dampen" parameter .... use a high value like 3 or more
times the monitor-interval to give all nodes the chance to detect the
dead target(s), that should help.
Does that actually help in this case? My understanding is that the
dampen parameter will delay the attribute change for each host, but
those delays will still tick down separately for each node, resulting in
exactly the same behavior, just delayed by dampen seconds.
I have had the same questions, and I was quite surprised to see this
issue wasn't really mentioned anywhere.
So far, I've been relying on the dampen parameter.
Here is my resource definition:
primitive ping-nq-sw-swsec ocf:pacemaker:ping \
params host_list="192.168.10.1 192.168.2.11 192.168.2.12"
dampen="35s" attempts="2" timeout="2" multiplier="100" \
op monitor interval="15s"
As I understand it, a node cannot trigger any transition until 35s
(dampen) had passed since this particular node lost a ping-node.
And by setting a monitor interval of 15s, I can be sure that within this
35s, all nodes should have marked that ping-node as dead and continue to
all have a common score => nothing moves (35s > 2*15s so at least all
nodes have pinged twice during the dampen delay)
Hope that helps.
--
Cheers,
Florian Crouzat
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