[Pacemaker] Manging Virtual Machine's resource

[Nitin]

On Mon, 2008-05-19 at 08:34 +0200, Andrew Beekhof wrote:
> On May 19, 2008, at 7:14 AM, Nitin wrote:
> 
> > On Fri, 2008-05-16 at 15:08 +0200, Andrew Beekhof wrote:
> >> On May 16, 2008, at 3:04 PM, Nitin wrote:
> >>
> >>> Hello,
> >>>
> >>> I would like to make my virtual machines (DomUs) resources to
> >>> participate in the HA cluster. Dom0 (Physical Host) may or may not
> >>> have
> >>> resources.
> >>>
> >>> To do this I would like to treat DomUs as *resource* in the  
> >>> cluster as
> >>> opposed to treating them as *nodes*. I am planning to write OCF
> >>> resource
> >>> agents for virtual machines. But I am not very sure about how to
> >>> make a
> >>> resource's resource to participate in the cluster.
> >>>
> >>> Is there any configuration in existing structure to achieve this??
> >>> If no
> >>> then please tell me how to go about creating a "container"  
> >>> resource in
> >>> CRM.
> >>
> >> Why not just use the Xen agent if you don't want them to be cluster
> >> nodes?
> >> Or do you mean that you want them to both be resources and to run
> >> other resources too?
> >
> > Yes. Please advise me how to go about it.
> > Thanks a lot for reply.
> 
> We don't have a clean way to do that yet
> 
> Possible options:
> a) start the services at VM boot (you don't get monitoring)
> b) start the services at VM boot and modify the Xen agent to monitor  
> the services inside the VM (ugly)
> c) add a proxy resource to start/stop/monitor the services inside the  
> VM (complex)
Did you mean writing a OCF RA which will take care of start/stop/monitor inside VMs ??
Can we configure how CRM will handle resource failures in this case?? 
For example if res1 at VM1 fails 
	     retry on same VM
		success --> OK
		failure --> start res1 (with group dependencies/collocation preferences) at VM2 on same node 
			(success -- OK)
			failure --> start res1 as direct resource to node 
			..........
			..........
			
			finally use Passive node's VM
			
				
	    
> d) implement a generic version of c)
I guess it would be required otherwise we have to write a proxy resource
(c) for each resource type. Right??

> e) have the VM join the cluster (makes stonith and quorum "interesting")
> f) wait for us to implement clusters-of-clusters which also solves  
> this scenario "for free"
> g) something else i've not thought of
> 
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