Hi; This IPMI fencing is the technology where most of cloud providers like OVirt use, so its good. How could we test this IPMI Fencing feature, where could i find its scripts and its usage/test documents? I have some test hardwares and i really like to try it.
Thanks Özhan On Sat, Oct 17, 2015 at 2:44 AM, ilya <ilya.mailing.li...@gmail.com> wrote: > Please see another thread on DEV that proposes the fix for KVM HA -> > [DISCUSS] KVM HA with IPMI Fencing > > > ---- > > We propose the following solution that in our understanding should cover > all use cases and provide a fencing mechanism. > > NOTE: Proposed IPMI fencing, is just a script. If you are using HP > hardware with ILO, it could be an ILO executable with specific > parameters. In theory - this can be *any* script not just IPMI. > > Please take few minutes to read this through, to avoid duplicate efforts... > > > Proposed FS below: > ---------------- > > > https://cwiki.apache.org/confluence/display/CLOUDSTACK/KVM+HA+with+IPMI+Fencing > > > On 10/12/15 12:54 AM, Frank Louwers wrote: > > > >> On 10 Oct 2015, at 12:35, Remi Bergsma <rberg...@schubergphilis.com> > wrote: > >> > >> Can you please explain what the issue is with KVM HA? In my tests, HA > starts all VMs just fine without the hypervisor coming back. At least that > is on current 4.6. Assuming a cluster of multiple nodes of course. It will > then do a neighbor check from another host in the same cluster. > >> > >> Also, malfunctioning NFS leads to corruption and therefore we fence a > box when the shared storage is unreliable. Combining primary and secondary > NFS is not a good idea for production in my opinion. > > > > Well, it depends how you look at it, and what your situation is. > > > > If you use 1 NFS export als primary storage (and only NFS), then yes, > the system works as one would expect, and doesn’t need to be fixed. > > > > However, HA is “not functioning” in any of these scenario’s: > > > > - you don’t use NFS as your only primary storage > > - you use more than one NFS primary storage > > > > Even worse: imagine you only use local storage as primary storage, but > have 1 NFS configured (as the UI “wizard” forces you to configure one). You > don’t have any active VM configured on the primary storage. You then > perform maintenance on the NFS storage, and take it offline… > > > > All your hosts will then reboot, resulting in major downtime, that’s > completely unnecessary. There’s not even an option to disable this at this > point… We’ve removed the reboot instructions from the HA script on all our > instances… > > > > Regards, > > > > Frank > > >
