[libvirt-users] VM migration upon shutdown in centos 7

[Michal Privoznik]

On 01/05/2018 12:00 PM, Raman Gupta wrote:
> Hi,
> 
> I have CentOS 7,  two node system which allows live VM migration between
> them. Live migration triggered from virsh is happily happening. I am using
> GlusterFS for replicating VM disk files.
> 
> Now I want to automatically do the live migration at the time of
> reboot/shutdown/halt of the host node and for this I have written a systemd
> service unit [vPreShutdownHook.service] and placed the live migration
> command in a migrate script which is invoked from this service unit. The
> migrate script is invoked but migration does not happen.
> If someone has some idea please help me to migrate VM upon shutdown.
> 
> 
> ######## vPreShutdownHook.service ###############
> 
> [Unit]
> Description=vPreShutdownHook
> Requires=network.target
> Requires=libvirtd.service
> Requires=dbus.service
> Requires=glusterd.service
> Requires=glusterfsd.service
> DefaultDependencies=no
> Before=shutdown.target reboot.target
> 
> [Service]
> Type=oneshot
> RemainAfterExit=true
> ExecStart=/bin/true
> ExecStop=/root/vm_migrate.sh
> 
> [Install]
> WantedBy=multi-user.target
> 
> 
> ########## Command to migrate ############
> /usr/bin/virsh migrate --verbose --p2p --tunneled --live  --compressed
> --comp-methods "mt"  --comp-mt-level 5 --comp-mt-threads 5
> --comp-mt-dthreads 5   MY_VM qemu+ssh://root@$node2/system

Does this command alone succeed?
BTW: unless really needed --live will only make the migration take longer.

I don't know enough about systemd but maybe it's not waiting for virsh
to finish? Can you try to get any logs to see what is going on actually?

Michal