On 18/06/14 12:32 PM, Alessandro Baggi wrote:
Ok, fencing is a requirement for a cluster for hardware failure. I've another question about this arg, but for software failure. Supposing to have a cluster of httpd installation on 6 virtualized hosts, each one on a different server. Suppose also that a guest (named host6) has a problem and can't start apache. With this scenario, the ipmi, ups are unnecessary. How to work fencing in this way? How to make fencing node?
Thanks in advance.
Alessandro.
I'm not sure I understand properly... You mean that you have 6 VMs which are nodes in a cluster, or 6 nodes, each hosting a VM you want to make HA?
If the VMs are themselves nodes, then you could use fence_virt as the primary fence method, which would power off/on the VM itself by talking to the hypervisor on the host. If that fails (say because the host itself fails), the use IPMI or PDU based fencing as a backup, in which case the host itself would be powered off/on (thus ensuring the VM on the host is down as well).
If the hardware servers themselves are the nodes, then the VMs are not a factor in the equation. Services, including VMs, will recover on another host after the fence has succeeded.