Comment 9 for bug 1307215

Correct. Attached is a juju-deployer config that reproduces the issue when used with the juju local provider and /var/lib/lxc in the host backed onto btrfs. If you deploy it and run juju destroy-environment --force -y local, it should fail.

This is because Ceph sees that /srv/ceph is on btrfs and makes use of it.

ubuntu@vagrant-local-machine-1:~$ mount
/dev/sda2 on / type btrfs (rw)

So you'll end up with lots of snapshots created by Ceph inside LXC. These will be visible by running `btrfs subvolume list /var/lib/lxc` in the host:

(.venv-ubuntu)vagrant@vagrant-ubuntu-trusty-64:~$ sudo btrfs subvolume list /var/lib/lxc
ID 256 gen 9268 top level 5 path @lxc
ID 257 gen 8126 top level 256 path juju-precise-template/rootfs
ID 285 gen 8006 top level 256 path juju-trusty-template/rootfs
ID 762 gen 9208 top level 256 path vagrant-local-machine-25/rootfs
ID 763 gen 9208 top level 256 path vagrant-local-machine-26/rootfs
ID 764 gen 9208 top level 256 path vagrant-local-machine-27/rootfs
ID 925 gen 9208 top level 256 path vagrant-local-machine-27/rootfs/srv/ceph/current
ID 934 gen 9208 top level 256 path vagrant-local-machine-26/rootfs/srv/ceph/current
ID 944 gen 9208 top level 256 path vagrant-local-machine-25/rootfs/srv/ceph/current
ID 951 gen 9208 top level 256 path vagrant-local-machine-26/rootfs/srv/ceph/snap_4426
ID 954 gen 9208 top level 256 path vagrant-local-machine-26/rootfs/srv/ceph/snap_4483
ID 957 gen 9208 top level 256 path vagrant-local-machine-25/rootfs/srv/ceph/snap_4767
ID 958 gen 9208 top level 256 path vagrant-local-machine-27/rootfs/srv/ceph/snap_5753
ID 959 gen 9208 top level 256 path vagrant-local-machine-25/rootfs/srv/ceph/snap_4845
ID 960 gen 9208 top level 256 path vagrant-local-machine-27/rootfs/srv/ceph/snap_5754