2015-11-23 15:10 GMT+03:00 Peter Krempa <pkrempa@redhat.com>:
The file should not exist prior to the snapshot. If you want to pre-create it (with correct size and format), you need to specify --reuse-external in that case. Virsh manual already documents that:
If --reuse-external is specified, and the snapshot XML requests an external snapshot with a destination of an existing file, then the destination must exist and be pre-created with correct format and metadata. The file is then reused; otherwise, a snapshot is refused to avoid losing contents of the existing files.
If file is not exists i get error: error: internal error: unable to execute QEMU command 'transaction': Could not open '/test.raw': Invalid argument -- Vasiliy Tolstov, e-mail: v.tolstov@selfip.ru