Running KVM version ?

Hi everyone,

This list seems to be a developer list, I didn't find any "users" list. So please forgive me if I'm at the wrong place.

I would like to know if there's a way to know the version of a running kvm process ?

I have some VMs running for 100+ days, and I would like to know if I need to restart them to run with a newer version of kvm.

Thank you a lot.

Florent

2015-04-09 15:27+0200, Florent B:

I don't think it exists, KVM is used mostly by programs and they are not sophisticated enough to communicate.
(or they are, which is why humans aren't invited)

qemu-discuss/libvirt-users/openstack-operators (whatever you face) or stack overflow are better for questions about virtualization.

I think you meant QEMU process. KVM is the kernel part and it can't change while any VM is running. (uname -r gives kernel version.)

There are at least four ways to get VM's QEMU version. I presume you are using at most libvirt.

1a) virsh
1. get name of the VM
2. # virsh qemu-monitor-command $name --hmp info version
1b) qemu monitor
1. access the monitor (if you don't use libvirt, you should know how)
2. (qemu) info version
(2+. curse and repent if you set up JSON monitor)

3) reading /proc/$pid/mem
1. get PID of the QEMU process
2. # cd /proc/$pid/
3. # offset=$((0xawk -F - '/r-x.*qemu/{print $1}' maps))
4. # dd skip=$offset if=mem bs=1 | strings | grep 'emulator version'

4) gdb
(You probably don't have debuginfo and the option above is easier.)

No need to know the version for that. You can take look when the binary was updated and compare it with process start time.