[Linux-HA] best practices monitoring services in Xen instances

[Sebastian Reitenbach]

Hi,

to remove complexity from my cluster, I am experimenting with Xen.
Starting and stopping the Xen resources via heartbeat works well already. 
I am a bit concerned about the services in the virtual machines, how is the 
best approach to monitor their availability?

I have some solutions, but would like to know what corresponds to best 
practice:

- install heartbeat in the virtual domains too, then monitor the resources 
within the xen instance, but I think this is counterproductive as I wanted 
to remove complexity from the cluster due to having less resources.

- monitor the services in the virtual domains using SNMP, or custom scripts, 
and in case sth. fails, crm_resource stop and setart it again. Well, custom 
scripts sounds a bit error prone.

- I don't know whether xen has the ability, but does the priviliged domain 
has the ability to query a given domU for the state of a process, and in 
case the state is just not the wanted one, restart the domU.

I think the last one, would be the best, but I have no idea, whether xen can 
do that at all. I played around with OpenVZ for a short while, that at least 
could do that. Any other ideas, comments, rants are very welcome.

kind regards
Sebastian