Bug #8821
Updated by Dmitry Smirnov almost 10 years ago
`/usr/bin/rbd` have few errors with "rbd default format".
With the following in "/etc/ceph/ceph.conf":
<pre>
[client]
rbd default format = 2
</pre>
it is impossible to create a new image with format=1 because "--image-format" is silently ignored:
<pre>
# rbd create rbd/temporary1 --size 20000 --image-format=1
# rbd info rbd/temporary1
rbd image 'temporary1':
size 20000 MB in 5000 objects
order 22 (4096 kB objects)
block_name_prefix: rbd_data.63cc412ae8944a
format: 2
features: layering, striping
stripe unit: 4096 kB
stripe count: 1
</pre>
In addition to this an image was created with striping which was not explicitly used in "rbd create" command.
Compare it to the following, without "rbd default format" in "ceph.conf":
<pre>
# rbd create rbd/temporary1 --size 20000 --image-format=2
# rbd info rbd/temporary1
rbd image 'temporary1':
size 20000 MB in 5000 objects
order 22 (4096 kB objects)
block_name_prefix: rbd_data.63c3ed2ae8944a
format: 2
features: layering
</pre>
"rbd default format" should not enforce striping unless given explicitly.
It would be best Remember that striping is not supported by kernel RBD client (at least not in Linux-3.14) so attempt to use the same defaults for rbdmap an image format 2 disregarding of where format was chosen (in command line or in ceph.conf file). with striping will lead to "feature set mismatch", "missing 20000000000".