Hello Olivier, first sorry Aleksandr for hijacking the thread, I am planning to buy some AP7900 right now for some hosts without management boards and wanted to tap on your experience with them: - Did the outlet switching work well with ovirt? - Did you need to modify anything in ovirt (eg. create custom fence agents)? - Why replace the master switches (old age?) - Are the AP7900 working well also? - What exactly do you mean by 'some additional hardware'? I suppose you mean the switch itself and not any additional things beside the switch?
Thanks, any input is really appreciated. On 19.01.2015 11:23, Olivier Navas wrote: > Hi ! > > As you pointed, it wouldn't be safe if ovirt only tried to communicate with > the host. > > This is why Ovirt (and other cluster software) include a way to power cycle > hosts. If host is not responding, for any reason (software or hardware > failure), before cluster migrates vms, host will be fenced (power off and on > again) by an other host in the cluster. > > You need some special hardware to manage power cycling, and you need to > configure it on "power management" section of host parameters. > > On the HP servers we use, we can configure ILO as power management method. > This way, Ovirt can control power of the hosts as if we used the server web > interface to power cycle the server. It works very well for us (since ovirt > 3.4 or 3.5) and does not require some additional hardware, but I think it > will not work if a hardware failure has an impact on ILO hardware (don't know > if it may happen). > > You also can add some specific hardware to manage power supplies. I used to > buy APC masterswitch (replaced by apc AP7900) for this purpose, but this > requires some additional hardware and is not as convenient as ILO (IMHO). > > In both cases, you have to ensure that you always provide power to your > servers, your switches, and your power management hardware with dual power > supplies, connected to different power lines, different UPS, and so on > because if a single power failure can turn off both your server and your > power cycle mechanism, then Ovirt won't be able to recover. > > > > > ----- Mail original ----- >> De: "Kostyrev Aleksandr" <kosty...@tutu.ru> >> À: users@ovirt.org >> Envoyé: Dimanche 18 Janvier 2015 11:17:27 >> Objet: [ovirt-users] ovirt 3.5 and power outages >> >> good day, everybody! >> I've got three node cluster with power management enabled. >> >> As far as I understood to restart vms on the other host in the cluster >> in case when host suffered from power outage >> the engine has to be able to connect to host (specifically to vdsm) to >> be sure that host has been rebooted and it's not running any vms. >> >> But what if I'm running a lot of vms on the host and it's 3 o'clock in >> the morning and >> 1) engine has rebooted the host but the host cannot boot because of some >> hardware problem or new kernel gives a kernel panic? >> 2) the host's motherboard burned out and it cannot get booted >> >> so the engine will never connect to host and therefore all the vms that >> were running on that host won't migrate to other node in the cluster. >> So my cluster in that case is useless 'cause I'm not there to press >> "confirm host has been rebooted'. >> >> -- >> С уважением, >> Костырев Александр, >> системный администратор >> _______________________________________________ >> Users mailing list >> Users@ovirt.org >> http://lists.ovirt.org/mailman/listinfo/users >> > > -- > Ce courriel et tous les fichiers attachés qu'il contient sont confidentiels > et destinés exclusivement à la personne à laquelle ils sont adressés. Si vous > avez reçu ce courriel par erreur, merci de le retourner à son expéditeur et > de le détruire. Il est rappelé que tout message électronique est susceptible > d'alteration au cours de son acheminement sur internet. Seuls les documents > officiels du SDIS sont de nature à engager sa responsabilité. Les idées ou > opinions présentées dans ce courriel sont celles de son auteur et ne > représentent pas nécessairement celles du SDIS de la Gironde. > _______________________________________________ > Users mailing list > Users@ovirt.org > http://lists.ovirt.org/mailman/listinfo/users > -- Daniel Helgenberger m box bewegtbild GmbH P: +49/30/2408781-22 F: +49/30/2408781-10 ACKERSTR. 19 D-10115 BERLIN www.m-box.de www.monkeymen.tv Geschäftsführer: Martin Retschitzegger / Michaela Göllner Handeslregister: Amtsgericht Charlottenburg / HRB 112767 _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
