On 12/06/2012 09:43 AM, Digimer wrote: > On 12/06/2012 03:26 AM, Lars Marowsky-Bree wrote: >> On 2012-12-06T00:02:28, Hermes Flying <[email protected]> wrote: >> >>> Hi, >>> I was wondering how does fencing/STONITH work in a VM environment? >>> Obviously the nodes running inside a VM should run in separate machines but >>> can we STONITH a node that is running inside a VM? >> >> I'd suggest to use something like SBD or fence_sanlock (depending on >> which distribution you run, we have multiple implementations of the >> wheel). > > fence_sanlock requires a "hardware" watchdog to work reliably. If you > can get the host/hypervisor to emulate one outside the VM, that should work. > > Alternatively, fence_xvm and fence_virsh would work. The trick is to > ensure multicast messages travel between the hardware nodes, so you need > to get your networking right. > >>> Also what is the best practice in regards to VMs and HA? >> >> If you're running HA *within* the VMs, just treat them like you'd treat >> physical nodes. Except for choosing an appropriate fencing mechanism, >> nothing special. >> >> Oh - if your hypervisor does something like live migrations, make sure >> the timeouts of the cluster don't trigger during one. But normally >> that's not a problem. > > Very important point. >
Forgot to link the fence_sanlock docs; https://alteeve.ca/w/Watchdog_Recovery -- 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
