Re: [Linux-HA] Need suggestion on STONITH device
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 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 >> Linux-HA@lists.linux-ha.org >> http://lists.linux-ha.org/mailman/listinfo/linux-ha >> See also: http://linux-ha.org/ReportingProblems >> > ___ > Linux-HA mailing list > Linux-HA@lists.linux-ha.org > http://lists.linux-ha.org/mailman/listinfo/linux-ha > See also: http://linux-ha.org/ReportingProblems > ___ Linux-HA mailing list Linux-HA@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
Re: [Linux-HA] Need suggestion on STONITH device
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. 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 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 > Linux-HA@lists.linux-ha.org > http://lists.linux-ha.org/mailman/listinfo/linux-ha > See also: http://linux-ha.org/ReportingProblems > ___ Linux-HA mailing list Linux-HA@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
Re: [Linux-HA] Need suggestion on STONITH device
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 Linux-HA@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
[Linux-HA] Need suggestion on STONITH device
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? Thanks ___ Linux-HA mailing list Linux-HA@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
