Cephfs charm does not work with Luminous clusters

[Erlon R. Cruz]

When the cephfs charm is installed with a ceph cluster that is
not Mimic, (Luminous or older), there is a inconsistency between
the fuse client Mimic and a Nautilus cluster. And trying to
mount a file system will result in an error like the following[1]:

an error occurred while running (93) setfattr [-n ceph.quota.max_bytes -v 134217728 /var/lib/kubelet/plugins/cephfs.csi.ceph.com/controller/volumes/root-csi-cephfs-pvc-f4ac4f8d-d81a-4aaf-9edd-36db14e52074/csi-volumes/csi-cephfs-pvc-f4ac4f8d-d81a-4aaf-9edd-36db14e52074-creating]: exit status 1: setfattr: /var/lib/kubelet/plugins/cephfs.csi.ceph.com/controller/volumes/root-csi-cephfs-pvc-f4ac4f8d-d81a-4aaf-9edd-36db14e52074/csi-volumes/csi-cephfs-pvc-f4ac4f8d-d81a-4aaf-9edd-36db14e52074-creating: Operation not supported

Observed enviornment[2].

[1] https://pastebin.ubuntu.com/p/7pV8Q2d8pG/
[2] https://pastebin.ubuntu.com/p/Ks6q566jYJ/

[Chris MacNaughton (chris.macnaughton)]

The CephFS charm is tested back to Jewel in it's functional gate with creation of multiple VMs and reading/writing to a CephFS share from both of them (https://github.com/openstack-charmers/zaza-openstack-tests/blob/137f80a09301fce149a6937974336f5587768c46/zaza/openstack/charm_tests/ceph/fs/tests.py#L52). The tests are using a bionic image so will have the ceph-fuse package installed from there.

[Chris MacNaughton (chris.macnaughton)]

I have just successfully mounted a CephFS share on Focal (Ceph Octopus) against a bionic (Luminous) cluster. I suspect that there is an issue with the ceph csi plugin's usage of CephFS that is causing issues, rather than CephFS (or the charm) itself