If the running VM contains a writable raw image, creating snapshot fails internally in QEMU, but the error is not detected by libvirt. Success is still reported to the user, who will see the snapshot in libvirt, even they are NOT created by qemu. virsh # qemu-monitor-command --hmp winxp-1 savevm \"test\" Device 'drive-fdc0-0-0' is writable but does not support snapshots. virsh # snapshot-create-as winxp-1 test Domain snapshot test created Since there is no QMP command in QEMU, libvirtd sends a HMP command to the running QEMU and parses the returned text. There only the following 4 strings are detected as errors: src/qemu/qemu_monitor_text.c:2822 # qemuMonitorTextCreateSnapshot() Since none of them match the above message, libvirt thinks the command succeeded. Add "does not support snapshots" as an additional error condition. Signed-off-by: Philipp Hahn <hahn(a)univention.de&gt; --- src/qemu/qemu_monitor_text.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/src/qemu/qemu_monitor_text.c b/src/qemu/qemu_monitor_text.c index bc0a11d..5880ab9 100644 --- a/src/qemu/qemu_monitor_text.c +++ b/src/qemu/qemu_monitor_text.c @@ -2854,6 +2854,10 @@ int qemuMonitorTextCreateSnapshot(qemuMonitorPtr mon, const char *name) virReportError(VIR_ERR_OPERATION_FAILED, "%s", reply); goto cleanup; } + else if (strstr(reply, "does not support snapshots") != NULL) { + virReportError(VIR_ERR_OPERATION_FAILED, "%s", reply); + goto cleanup; + } ret = 0; -- 1.7.10.4