On Wed, 2017-03-29 at 13:20 -0500, Robert Nichols wrote: > > OK, I think I get the idea. The manpage is not only unclear, it's > > actually inconsistent with what you say. There is no mention of a '-b' > > option to 'create'. The --help option doesn't say anything about it > > either, but I tried it and it works. > > Indeed! The manpage does say, "If the option backing_file is specified, ..." in the section for the "create" command, but does not, in that section, mention how to specify it. > > Quite ... > ... > > > > OK, once I've created the backing file, how do I use it? I've been > > running virt-manager for everything but it's not clear how to do this. > > Do I need to run qemu-kvm from the command line? > > You don't _create_ the backing file. You _use_ an existing image _as_ a backing file. What you create is a new file, let's call it a "virtual image", which you can then use just like any other disk image in a VM. If you're using virt-manager, you can create a new VM and select "Import existing disk image" as the source. Or, you can edit your existing VM instance and substitute the new "virtual image" file for whatever it is using now. Right, I'll give that a go. poc _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx