I am running some qemu-kvm virtual machines via libvirt using Ceph RBD as the back-end
storage. Today I was testing an update to libvirt-1.0.6 on one of my hosts and discovered
that it includes this change:
[libvirt] [PATCH] Forbid use of ':' in RBD pool names
...People are known to be abusing the lack of escaping in current libvirt to pass
arbitrary args to QEMU.
I am one of those people--I have been storing colon-separated arguments in my disk source
'name' attribute to control the RBD cache settings on a per-volume basis. Under
libvirt-1.0.6 such VM's refuse to start:
error: Failed to start domain foo
error: unsupported configuration: ':' not allowed in RBD source volume name
'mypool/foo:rbd_cache_size=268435456:rbd_cache_max_dirty=134217728:rbd_cache_target_dirty=33554432:rbd_cache_max_dirty_age=5'
So my question is how do I control the cache settings now?
Thanks,
JN