Files left over after removing KVM guest

kvm-virtualizationqemuvirshvirtualization

Looking at this post I ran the following commands to remove a VM:

sudo rm /var/lib/libvirt/images/centos01.qcow2
sudo virsh undefine centos01 --managed-save --snapshots-metadata

But it looks like I still have some files pertaining to this image present:

find /var -name centos*
/var/log/libvirt/qemu/centos01.log
/var/lib/libvirt/qemu/centos01.monitor

Should I just delete these files? Will I run into a problem if I create a new VM with the same name?

Also, what is a .monitor file? I haven't been able to find much info about what they do.

Best Answer

These files are safe to delete as long as the corresponding VM is not running.

The log files are never deleted automatically when you undefine a VM; you can rotate or delete them yourself.

And the monitor is a socket by which you can connect to the VM's internal qemu monitor. Not somehting you need if the VM no longer exists, and you don't normally use it anyway.

Related Solutions

Linux – mount qcow2 snapshots

You should apply the snapshot and mount the image like always. It's better to create a snapshot right before applying if you want to turn back to the original disk contents before you do these operations. After you apply the snapshot you just mount the image with qemu-nbd as always:

# modprobe nbd max_part=8
$ qemu-img snapshot -c backup image.qcow2
$ qemu-img snapshot -a old_snapshot image.qcow2
$ qemu-nbd --connect=/dev/nbd0 image.qcow2
# mount /dev/nbd0p1 /mnt

You might want to save snapshot separately and mount it as another disk drive. For this you should use convert comand for qemu-img.

$ qemu-img convert -s old_snapshot image.qcow2 old_snapshot.qcow2
$ qemu-nbd --connect=/dev/nbd0 old_snapshot.qcow2
# mount /dev/nbd0p1 /mnt

See man qemu-img(1) and qemu-nbd(1) for more details.

Snapshot/rollback in Kvm using DRBD

I believe the XML file is just something virsh creates for the own bookkeeping and thus redundant.

You should be able to see the snapshot information in the qcow2 file using the qemu-img info <filename> command and revert to them using qemu-img snapshot -a <snapshot-name> <filename>.

Edit: according to the docs, a memory snapshot should have been created as well when using virsh create-snapshot. I have no idea where this one is going, but if you want more than just disk states, you should take care of the XML file to be copied as well - maybe by creating a symlink for /var/lib/libvirt/qemu/snapshot/vm/ to point at a directory in your DRBD-replicated volume.

Best Answer

Related Solutions

Linux – mount qcow2 snapshots

Snapshot/rollback in Kvm using DRBD

Related Topic