On Tue, 2017-03-28 at 12:38 -0500, Robert Nichols wrote: > > > What you have is not a snapshot. A snapshot is created with "qemu-img > > > snapshot -c <snapshot-name> <imagename>", and that is _not_ a separate > > > file. That "<snapshot-name>" is not a file name but just a tag to > > > identify one of possibly several snapshots within that "<imagename>" file. > > > > I did create it with the above line. Clearly I didn't understand where > > it was, or perhaps I inadvertently deleted it. > > That output from "qemu-img info ..." says otherwise. That > /var/lib/libvirt/images/Windows10.qcow2 file was created with "qemu-img > create -b /home/poc/Win10/win10.qcow2 > /var/lib/libvirt/images/Windows10.qcow2". There is no other way that "backing > file: /home/poc/Win10/win10.qcow2" could appear in the output.
I can only say I have no recollection of typing that, and that I did want to create a snapshot as a test. But it was a few days ago so I may be wrong. > In order for the .../Windows10.qcow2 file to be valid, that backing file > _must_ exist and be unchanged since that new file was created. OK, though I can't guarantee it hasn't changed since I did run the VM afterwards. > > Currently 'qemu-img snapshot -l <filename>' gives no output, so it > > looks like it's gone assuming it was ever there. > > There should not be any output. You simply do not have anything that qemu-img > calls a "snapshot". > > > (BTW the "no such file or directory" message could not be less > > helpful). > > Agreed, 100%. > > > > What you made was a copy-on-write image using /home/poc/Win10/win10.qcow2 > > > as a backing file. You can make changes in > > > /var/lib/libvirt/images/Windows10.qcow2 and not affect the backing file, > > > but the backing file _must_not_be_changed_ during the lifetime of that > > > dependent image. That c-o-w image cannot be restored to its original > > > state. The way you do that is to throw it away and create a new one with > > > the same backing file. > > > > I'm going to try to attach it to another Windows instance to see if it > > can be repaired. Otherwise, it looks like I'm screwed. > > That backing file _must_ exist, or else you have nothing. If the backing file > exists, but has changed, then the only valid image is what is currently in > the backing file. If an unchanged backing file exists, you have the option to > (a) throw away that /var/lib/libvirt/images/Windows10.qcow2 file and create > it anew from that backing file, or (b) merge the changes that have been made > in the /var/lib/libvirt/images/Windows10.qcow2 file back into the backing > file. You do the latter with "qemu-img commit > /var/lib/libvirt/images/Windows10.qcow2". OK, I'll look into that. Thanks again. poc _______________________________________________ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-le...@lists.fedoraproject.org
