I see, I will look into this. There is one thing I am confused about. If I have Node-A/Node-B/Node-C and let's say Node-A has the VIP. What happens if corosync fails in all nodes? Will all 3 try to kill eachother?
________________________________ From: Digimer <[email protected]> To: Hermes Flying <[email protected]> Cc: General Linux-HA mailing list <[email protected]> Sent: Monday, December 3, 2012 1:20 PM Subject: Re: [Linux-HA] Corosync on cluster with 3+ nodes Most Fujitsu servers work with fence_ipmilan. I suspect the same is true with the IBM servers. Ask the hardware people if they have out-of-band management on the servers (which is the generic/marketing way of saying IPMI or the like). On 12/03/2012 05:00 AM, Hermes Flying wrote: > Some are IBM servers mentioning VMK (optional) and others are Fujitsu > mentioning iRMC. > Not sure what can I do in the IBM case > > > ------------------------------------------------------------------------ > *From:* Digimer <[email protected]> > *To:* Hermes Flying <[email protected]> > *Cc:* General Linux-HA mailing list <[email protected]> > *Sent:* Sunday, December 2, 2012 10:36 PM > *Subject:* Re: [Linux-HA] Corosync on cluster with 3+ nodes > > I don't know anything about your setup or office situation, so I can't > speak to your specific issues. > > What I can say is that almost all actual servers have remote management; > Fujitsu servers have IPMI, HP servers have iLO, Dell servers have DRAC, > IBM servers have RSA and so on. Most generic servers have at least basic > IPMI. So it's very likely that you will already have what you need to > implement fencing. If you don't, then something like the APC AP7900 is > usually about $500 canadian and will work as a fence device. I don't > know what country you are in, so I can't speak more on availability, > applicability or cost. > > You might seriously want to consider hiring someone to help you with > this setup. Clustering is not a straight-forward topic. The cost to hire > a consultant might save you enough time and headache that it's cheaper > in the end than trying to do it yourself. > > On 12/02/2012 03:31 PM, Hermes Flying wrote: >> I am an application developer and so far I didn't care about HW specs >> (not my responsibility). >> Now it seems I must care and so since I am not sure what HW is being >> recommended for servers I will verify tomorrow and let you know. >> My concern is that by going to pacemaker (although seems to be exactly >> what I need) is that we would need to request for new HW on migrate to >> new deployment. I don't even know if these devices are expensive. >> Did you ever had an issue with this? If I have problem with this, should >> I be looking into different solution? Any suggestion for alternative? >> >> >> ------------------------------------------------------------------------ >> *From:* Digimer <[email protected] <mailto:[email protected]>> >> *To:* Hermes Flying <[email protected] > <mailto:[email protected]>> >> *Cc:* General Linux-HA mailing list <[email protected] > <mailto:[email protected]>> >> *Sent:* Sunday, December 2, 2012 10:19 PM >> *Subject:* Re: [Linux-HA] Corosync on cluster with 3+ nodes >> >> It must be an external device. If, for example, the kernel crashes hard, >> or if you get a spinlock, the system may not respond to anything or a >> service may never stop, blocking a reboot. You can not trust that the >> system is accessible or functioning in any way. >> >> Fencing *must* be an external device. Period. >> >> What kind of servers do you have? >> >> On 12/02/2012 03:15 PM, Hermes Flying wrote: >>> If I have a requirement not to include external HW, is there any other >>> way? I mean, I am not -by far- a linux expert, but how come it doesn't >>> do a restart or halt? >>> >>> >>> ------------------------------------------------------------------------ >>> *From:* Digimer <[email protected] <mailto:[email protected]> > <mailto:[email protected] <mailto:[email protected]>>> >>> *To:* Hermes Flying <[email protected] > <mailto:[email protected]> >> <mailto:[email protected] <mailto:[email protected]>>> >>> *Cc:* General Linux-HA mailing list <[email protected] > <mailto:[email protected]> >> <mailto:[email protected] <mailto:[email protected]>>> >>> *Sent:* Sunday, December 2, 2012 10:01 PM >>> *Subject:* Re: [Linux-HA] Corosync on cluster with 3+ nodes >>> >>> On 12/02/2012 02:56 PM, Hermes Flying wrote: >>>> Clear! In order to do fence and crash a node, is there a specific HW >>>> requirement to do this? >>> >>> Yes, there must be external hardware (out-of-band management counts as >>> "external", despite physically being on the server's mainboard). The >>> most common fence device is IPMI, iLO, RSA, iDRAC and the like. >>> Alternatives are switched PDUs, like APC's AP7900. >>> >>> -- >>> Digimer >>> Papers and Projects: https://alteeve.ca/w/ >>> What if the cure for cancer is trapped in the mind of a person without >>> access to education? >>> >>> >> >> >> -- >> Digimer >> Papers and Projects: https://alteeve.ca/w/ >> What if the cure for cancer is trapped in the mind of a person without >> access to education? >> >> > > > -- > Digimer > Papers and Projects: https://alteeve.ca/w/ > What if the cure for cancer is trapped in the mind of a person without > access to education? > > -- Digimer Papers and Projects: https://alteeve.ca/w/ What if the cure for cancer is trapped in the mind of a person without access to education? _______________________________________________ Linux-HA mailing list [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
