<div dir="ltr"><div>Understood everything except</div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">or by waiting for an event with event (the progress of a pull model backup is under the control of whatever third party connects to the NBD export)</blockquote><br><div>How do I wait for an event with event. Can you please give an example.</div><div><br></div><div>However, the clarification till now is sufficient for me. Specially the link was very helpful.</div><div><br></div><div>One more thing, There are some documents which say: </div><div><pre style="white-space:pre-wrap"><code>backup-begin <domain> [--backupxml <string>] [--checkpointxml <string>] [--reuse-external]</code></pre><pre style="white-space:pre-wrap"><span style="font-family:Arial,Helvetica,sans-serif;white-space:normal">There are others which say:</span><br></pre><pre style="white-space:pre-wrap">backup-begin domain [backupxml] [checkpointxml] [--reuse-external]<span style="font-family:Arial,Helvetica,sans-serif;white-space:normal"><br></span></pre><pre style="white-space:pre-wrap"><span style="font-family:Arial,Helvetica,sans-serif;white-space:normal">Which syntax is right?</span></pre></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sat, Jan 15, 2022 at 3:19 AM Peter Krempa <<a href="mailto:pkrempa@redhat.com">pkrempa@redhat.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On Fri, Jan 14, 2022 at 23:39:10 +0600, Ahmad Ismail wrote:<br>
> Normally when I backup a kvm machine I shutdown the machine then run:<br>
<br>
[...]<br>
<br>
> The problem with this help is, it is not clear enough.<br>
> <br>
> I understand that I should use virsh backup-begin vm1 to backup a live kvm<br>
> machine. However, this command only create .qcow2 files. What about the .xml<br>
> file.<br>
> <br>
> What does --backupxml , --checkpointxml & --reuse-external actually do?<br>
> <br>
> When should I use them?<br>
<br>
'man virsh' states:<br>
<br>
backup-begin<br>
Syntax:<br>
<br>
backup-begin domain [backupxml] [checkpointxml] [--reuse-external]<br>
<br>
Begin a new backup job. If backupxml is omitted, this defaults to<br>
a full backup using a push model to filenames generated by lib‐<br>
virt; supplying XML allows fine-tuning such as requesting an in‐<br>
cremental backup relative to an earlier checkpoint, controlling<br>
which disks participate or which filenames are involved, or re‐<br>
questing the use of a pull model backup. The backup-dumpxml com‐<br>
mand shows any resulting values assigned by libvirt. For more in‐<br>
formation on backup XML, see:<br>
<a href="https://libvirt.org/formatbackup.html" rel="noreferrer" target="_blank">https://libvirt.org/formatbackup.html</a><br>
<br>
If --reuse-external is used it instructs libvirt to reuse tempo‐<br>
rary and output files provided by the user in backupxml.<br>
<br>
If checkpointxml is specified, a second file with a top-level ele‐<br>
ment of domaincheckpoint is used to create a simultaneous check‐<br>
point, for doing a later incremental backup relative to the time<br>
the backup was created. See checkpoint-create for more details on<br>
checkpoints.<br>
<br>
This command returns as soon as possible, and the backup job runs<br>
in the background; the progress of a push model backup can be<br>
checked with domjobinfo or by waiting for an event with event (the<br>
progress of a pull model backup is under the control of whatever<br>
third party connects to the NBD export). The job is ended with<br>
domjobabort.<br>
<br>
<br>
Does this clarify it sufficiently?<br>
<br>
</blockquote></div>