[CentOS-virt] Fencing question(s)

Thu Jun 21 17:43:46 UTC 2012
Digimer <lists at alteeve.ca>

On 06/21/2012 01:01 PM, Steve Campbell wrote:
> I've got a Centos 5.8 box that I use for testing Xen VMs. I'm trying to
> setup some Centos 6.2 hosts in a high availability situation. I've tried
> the pacemaker route and couldn't get the connection established, so
> thought I'd try the RH-preferred methods. Mind you, all of these VMs are
> on the same host.
> Using Conga, it seems that I need some sort of fencing device, which
> doesn't really work in a VM environment. I'm guessing it's the same with
> command line configuration.
> Firstly, is it really possible to set up two VMs on the same machine to
> do HA? I can't see why not, but I'm not the best source of knowledge on
> any of this.
> Secondly, is there a useable fencing device that would work in a virtual
> environment for me to test with? I'd really like to avoid fencing
> altogether, even once in production, but every thing I read suggests
> against that.
> Any type of reply would be appreciated.
> steve campbell

"HA" on the same node is kind of contradictory. However, yes, you can 
build (and fence) a cluster of VMs on the same host. Look at fence_xvm 
or fence_virsh.

Can you use two servers? If so, you can build a truly HA cluster for 
your VMs;


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