vzdump: increase timeout for QMP 'cont' after backup start

Since 'backup' can now work asynchronously, QEMU may not be ready to
receive the next QMP command ('cont') immediately. Thus, increase the
timeout, to avoid aborted backups in slow environments.

There may be a deeper QEMU bug hidden under the covers here too, but at
least one user reported success with simply increasing the timeout:
https://forum.proxmox.com/threads/pve7-pbs2-backup-timeout-qmp-command-cont-failed-got-timeout.95212/page-2#post-426261

See also:
https://bugzilla.proxmox.com/show_bug.cgi?id=3693
https://forum.proxmox.com/threads/problem-seit-update-auf-7-0.97388/
https://forum.proxmox.com/threads/error-with-backup-when-backing-up-qmp-command-query-backup-failed-got-wrong-command-id.88017/page-3#post-416339

Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>

diff --git a/PVE/VZDump/QemuServer.pm b/PVE/VZDump/QemuServer.pm
index b133694d45d7295e89738d93b07e94d5e12768a0..17cf7245802c75ea0f6cd6fe481abc9454350acf 100644 (file)
--- a/PVE/VZDump/QemuServer.pm
+++ b/PVE/VZDump/QemuServer.pm
@@ -867,7 +867,7 @@ sub resume_vm_after_job_start {
     } else {
        $self->loginfo("resuming VM again");
     }
-    mon_cmd($vmid, 'cont');
+    mon_cmd($vmid, 'cont', timeout => 45);
 }
 
 # stop again if VM was not running before