CephFS MultiFS: Users don't know the name of the filesystem to use when mounting shares

[Goutham Pacha Ravi]

This is an extension of https://bugs.launchpad.net/manila/+bug/2049538

As the other bug records,

Ceph supports multiple cephfs filesystems since the Pacific release [1][2]. This functionality allows configuring separate file systems with full data separation on separate pools. Alongside data separation, each filesystem has its own metadata pools as well as metadata server/s. OpenStack Manila users benefit from this level of isolation by mapping an isolated filesystem to a separate backend. This means that you could have multiple backends configured in Manila provisioning onto the same ceph cluster, but each within its own CephFS filesystem.

The CephFS driver permits this by the use of a configuration option: ``cephfs_filesystem_name`` [3].

When the filesystem isn't called "cephfs", users/automation software will need to specify the filesystem name when mounting subvolumes (manila shares). This issue was discussed at the Oct 2023 (Caracal) PTG [4]. One solution was for the driver to set the filesystem name as the share's metadata so users and automation tools can view this information. This issue is reported as a separate RFE:

[1] https://docs.ceph.com/en/pacific/cephfs/multifs/
[2] https://docs.ceph.com/en/latest/cephfs/multifs/
[3] https://opendev.org/openstack/manila/src/commit/2c2788fa2de7c5b7b02e4d131a9a6c88fc34fc18/manila/share/drivers/cephfs/driver.py#L138
[4] https://etherpad.opendev.org/p/caracal-ptg-manila-cephfs

[Vida Haririan (vhariria)]

See additional discussions at https://meetings.opendev.org/meetings/manila/2024/manila.2024-01-25-15.00.log.html

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/manila/+/909175

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/manila/+/909916

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/manila/+/909175
Committed: https://opendev.org/openstack/manila/commit/3429717601eadc8fd62e570b28a36e1989f677f2
Submitter: "Zuul (22348)"
Branch: master

commit 3429717601eadc8fd62e570b28a36e1989f677f2
Author: silvacarloss <email address hidden>
Date: Thu Feb 15 20:26:24 2024 -0300

    Add a new config option to specify admin metadata

    - A new config option named ``admin_metadata_keys`` was introduced
    and we expect it to be set in the DEFAULT section of the manila
    configuration file. It is expected that administrators will provide
    a list of metadata keys that can only be updated by administrators
    through this configuration option.

    - Drivers will be able to set metadata while creating shares
    through the `get_optional_share_creation_data` driver interface.

    Closes-Bug: #2050010
    Change-Id: I6412710c7db89747d23033e1a5a6be9de5886b0b

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/manila/+/909916
Committed: https://opendev.org/openstack/manila/commit/7e585a3bb56bf22fedd6cae1cf942d42d35c9b89
Submitter: "Zuul (22348)"
Branch: master

commit 7e585a3bb56bf22fedd6cae1cf942d42d35c9b89
Author: silvacarloss <email address hidden>
Date: Thu Feb 22 14:38:26 2024 -0300

    Add cephfs filesystem to shares metadata

    Make use of the `get_optional_share_creation_data` driver interface
    to metadata in shares' created using the cephfs protocol.

    Closes-Bug: #2050010
    Change-Id: I91b51f974840f593334f2dcddfcfd45adfe87780

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/manila/+/912300
Committed: https://opendev.org/openstack/manila/commit/987352d6cbcc6ead3c1e5c4ad9948b59b71c57fb
Submitter: "Zuul (22348)"
Branch: master

commit 987352d6cbcc6ead3c1e5c4ad9948b59b71c57fb
Author: silvacarloss <email address hidden>
Date: Fri Mar 8 15:47:05 2024 -0300

    Change admin metadata config option name

    This change is a follow-up to a change that merged recently [1].
    We are changing the name of the config option to make it similar
    to the policy we have defined for updating some metadata that
    should only be manipulated by administrators.

    [1] https://review.opendev.org/c/openstack/manila/+/909175

    Related-Bug: #2050010
    Change-Id: I9a8a27f1181b92291f2d4ad5fd9d4483e2dacc50

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/manila 18.0.0.0rc1 release candidate.