Re: [libvirt] [PATCH] rbd: Open in Read-Only mode when refreshing a volume

By opening a RBD volume in Read-Only we do not register a watcher on the header object inside the Ceph cluster. Refreshing a volume only calls rbd_stat() which is a operation which does not write to a RBD image. This allows us to use a cephx user which has no write permissions if we would want to use the libvirt storage pool for informational purposes only. It also saves us a write into the Ceph cluster which should speed up refreshing a RBD pool. rbd_open_read_only() is available in all librbd versions which also support rbd_open(). Signed-off-by: Wido den Hollander <wido(a)widodh.nl&gt; --- src/storage/storage_backend_rbd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)