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<font face="SFNS Display">Hi,<br>
<br>
</font><font face="SFNS Display">in my installation I'm going to use
volumes to boot instances, not ephemeral disks. And I faced
unexpected (for me, at least) behaviour when trying to implement
snapshoting: image, created with "openstack server image create"
can't be used for boot from volume, i.e.<br>
</font><br>
I <font face="SFNS Display">create image using "</font><font
face="SFNS Display"><font face="SFNS Display">openstack server
image create --name jsnap jex-n1" and then</font></font><font
face="SFNS Display">:<br>
<br>
- creating server using ephemeral disk<br>
* openstack server create jTest [ ... ] --image jsnap<br>
is <b>OK</b><br>
<br>
- creating server using</font><font face="SFNS Display"> volume,
populated from image:<br>
* openstack volume create jVol --size 8 <b>--image jsnap</b>
--bootable</font><font face="SFNS Display"><br>
* openstack server create jTest [ ... ] --volume jVol<br>
<b>FAIL</b><b>S</b> with the following error: "<u>Invalid image
metadata. Error: A list is required in field
img_block_device_mapping, not a unicode (HTTP 400)</u>".<br>
<br>
- creating server using volume, populated from snapshot (which
corresponds to the image):<br>
* openstack volume create jVol --size 8 <b>--snapshot
f0ad0bf0-97f4-49df-b334-71b9eb639567</b> --bootable</font><br>
<font face="SFNS Display"><font face="SFNS Display">* </font></font><font
face="SFNS Display"><font face="SFNS Display"><font face="SFNS
Display">openstack server create jTest [ ... ] --volume jVol<br>
</font></font></font>is <b>OK</b><br>
<br>
Assuming this is correct (oh, really? can't find this topic in
documentation), I don't need image as it's senseless entity (I can't
use it for booting from volumes) and just need snapshot. But I still
like
<a class="moz-txt-link-freetext" href="https://blueprints.launchpad.net/nova/+spec/quiesced-image-snapshots-with-qemu-guest-agent">https://blueprints.launchpad.net/nova/+spec/quiesced-image-snapshots-with-qemu-guest-agent</a>
so there are two questions regarding this:<br>
<br>
1) whether the following sequence will do exactly the same as
"server image create" does? -<br>
- "manually" freeze VM filesystem (using "<span class="line"><span
class="string">guest-fsfreeze-freeze</span></span>" command)<br>
- create snapshot using "openstack volume snapshot create --volume
<volume name> --force <snapshot name>"<br>
- "manually" unfreeze VM filesystem (using "<span class="line"><span
class="string">guest-fsfreeze-thaw</span></span>" command)<br>
<br>
2) and, when using Cinder API, is there way to synchronously wait
for end of snapshot creation? It's useful in order to thaw
filesystem immediately after snapshot will be done - neither after
nor before few seconds.<br>
<br>
Thanks.<br>
<br>
<pre class="moz-signature" cols="72">--
Volodymyr Litovka
"Vision without Execution is Hallucination." -- Thomas Edison
</pre>
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