On 04/01/2010 08:54 PM, Tony Gan wrote: > Thank you for your reply, Dominik. > I think UPS or PDU in this case is a better solution than a lights-out > device, since they have separate power supply.
They do? They _are_ the power supply for the node. So if the PDU supply is off, the node is off. I have not seen a PDU with multiple inputs yet (but there may be such device, I am no expert on that). Regards Dominik > And I don't think we need to manage UPS or PDU's failure by our self, the > manufacturer should take responsibility of this. Am I correct? > > > But yes, probably need additional budgets for this. > > Anyway, again, thanks for your advice. I'm going to do some research on > them. > > > > On Thu, Apr 1, 2010 at 6:38 AM, Dominik Klein <[email protected]> wrote: > >> Tony Gan wrote: >>> Hi, >>> For a two-node cluster, what are the best STONITH devices? >>> >>> Currently I am using Dell's iDrac for STONITH device. It works pretty >> well. >>> However the biggest problem for iDrac or any other lights-out devices is >>> that they share power supply with hosts machines. >>> >>> Once an active machine lost its power completely, you want to fail-over >> to >>> the backup-node in your cluster. >>> But with iDrac as your STONITH device you can not, because the STONITH >>> resource on backup node will run into error (fail to connect to STONITH >>> device, it's out of power too) , and refuse to start any resources. >>> >>> >>> I was wondering what kind of STONITH devices everybody is using to solve >>> this problem. And how much are they? >>> >>> Actually Pacemaker's page have a link talking about this: >>> http://www.clusterlabs.org/doc/crm_fencing.html >>> >>> It suggests UPS (Uninterruptible Power Supply) as well as PDU (Power >>> Distribution Unit). >>> Anybody used them before? How well are they integrated with Heartbeat? >> What >>> are the pros and cons? >> >> Hi >> >> I am using APC PDUs for my clusters. >> >> The setup is like: >> >> power supply circuit 1 -> pdu 1 -> node 1 >> power supply circuit 2 -> pdu 2 -> node 2 >> >> If a node fails, the corresponding pdu usually is accessible and >> manageable. >> >> However, if a pdu fails (and they probably can fail in ways we cannot >> really imagine (to quote Dejan)) that renders the same problem as yours. >> The node is down, the stonith device is down, so no resource takeover. >> >> But imho, this is not resolvable. At least I do not know of a way how >> to. If a PDU or UPS fails (node down and power device down), then the >> resources for the failed node will not be recovered since the failed >> node cannot be shot. >> >> Regards >> Dominik >> _______________________________________________ >> Linux-HA mailing list >> [email protected] >> http://lists.linux-ha.org/mailman/listinfo/linux-ha >> See also: http://linux-ha.org/ReportingProblems >> > _______________________________________________ > Linux-HA mailing list > [email protected] > http://lists.linux-ha.org/mailman/listinfo/linux-ha > See also: http://linux-ha.org/ReportingProblems > _______________________________________________ Linux-HA mailing list [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
