Ok, thanks. I'll dig into this further and do some test runs. Is there a libvirt/kvm/clustering specific mailing list I could take this to should I run into issues?
On Mon, Feb 21, 2011 at 4:22 AM, Josip Deanovic <djosip+n...@linuxpages.net> wrote: > On Sunday 2011-02-20, Kenneth Armstrong wrote: >> Ok, so rebooting from within the guest OS itself might not be bad, >> since the PID remains the same? So RHCS is basically checking for the >> PID on a vm's instance then? > > AFAIK, RHCS is checking the state of a VM using virsh. > > So if you poweroff/power on your vm there is a chance for rgmanager to get > the status while your VM is "shut off", although it's a very short time. > > About the PID of a VM... > Generally rgmanager is using a good logic. In case you add your VM to > cluster configuration, start VM manually using virsh and then you try to > start it through clusvcadm, rgamnager will check all the nodes and if it > find out VM is already running, rgmanager will not start another instance of > your VM. It will just print out warning and inform you that your VM is now > started on some specific node. > > Because RHCS is using virsh to check the state of VMs, there is also a > danger of restarting libvirtd through nodes in a cluster. > Documentation of rgmanager states that if you want to restart (or stop) > libvirtd daemon, you must freeze VMs on that node. > Freezing of VMs doesn't mean VMs will be blocked, it means cluster will stop > checking the state of these VMs (domains) until your unfreeze them. > > Check these links for details about rgmanager: > http://sourceware.org/cluster/wiki/VirtualMachineBehaviors > http://sourceware.org/cluster/wiki/RGManager > > > P.S. > This is now a bit out of the scope of thid mailinglist. > > > -- > Josip Deanovic > _______________________________________________ virt-tools-list mailing list virt-tools-list@redhat.com https://www.redhat.com/mailman/listinfo/virt-tools-list
