On Fri, 2008-01-04 at 09:02 +0100, Alain Moulle wrote: > Hi Lon, > > Finally, I adopt this quorum disk configuration : > > <quorumd interval="1" label="QDISK0" min_score="1" tko="10" votes="1"> > <heuristic interval=2 tko="3" program="ping -t1 -c1 172.21.1.12" score=1/> > <heuristic interval=2 program="ping -t3 -c1 172.21.1.12" score=1/> > </quorumd> > > > I just wonder if the interval values for quorum disk with regard to > the one for heuristic is the best choice or not ? * should have quotes around attr values: interval=2 -> interval="2" score=1 -> score="1" * -cX is the number of pings to send. When using -c1, you should use tko="3" or something similar. * -tX is internet time to live - usually the number of router hops. For a local gateway, X should be 1. > And which are the rules to fit the good value for interval and tko > on heuristic ? (I don't completely understand why your both heuristics > avoids suicide if one ping get lots, it seems to be due to tko value > but ... ) 1. <heuristic interval="2" tko="3" program="ping -t1 -c1 172.21.1.12" score="1"/> "Send one ping 172.21.1.12 one time with a max IP TTL of 1. Do this every 2 seconds. If this execution fails 3 times, we're done." 2. <heuristic interval="2" program="ping -t1 -c1 172.21.1.12" score="1"/> "Ping 172.21.1.12 one time. Do this every 2 seconds. If we fail to get a response from this operation, we're done." 3. <heuristic interval="2" program="ping -t1 -c3 172.21.1.12" score="1"/> "Send 3 pings to 172.21.1.12. Do this every 2 seconds. If we fail to get a response from this operation, we are done." ... 1 and 3 are almost equivalent: 3 ping packets must be lost to decide the heuristic is dead. ... 2, however, means that if the ping packet is /ever/ lost, the heuristic is dead. -- Lon -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
