kolla/specs/kolla-ceph-bluestore.rst

3.5 KiB

Allow Kolla Ceph to deploy bluestore OSDs

https://blueprints.launchpad.net/kolla/+spec/kolla-ceph-bluestore

Kolla Ceph currently only supports filestore. In Queens release, the version of Ceph is Luminous, and the bluestore is the default store type. See [1].

This spec suggests to allow Kolla Ceph to deploy bluestore OSDs by default, and make the store type configurable.

Problem description

In Ceph Luminous, the bluestore is the default store type when deploy Ceph. As Kolla Ceph currently only supports filestore, so it is not aligned with Ceph default behaviour. We should support both filestore and bluestore in Kolla Ceph.

In Ceph bluestore, there are up to three partitions belong to one Ceph OSD, they are used for block, block.wal and block.db. We should support to activate the three partitions when deploy Ceph bluestore OSDs if the corresponding labels are defined and associated with the physical devices.

Use cases

1. Deploy Kolla Ceph and enable bluestore as default (the default value of the parameter ceph_osd_store_type is bluestore in /etc/kolla/globals.yml) 2. Deploy Kolla Ceph and enable filestore in the configuration file (change the value of the parameter ceph_osd_store_type to filestore in /etc/kolla/globals.yml)

Proposed change

Exposing the store type

Define new configuration parameter ceph_osd_store_type in Kolla configuration file /etc/kolla/globals.yml to indicate the store type used in Kolla Ceph.

Existing Kolla Containers

In the existing Ceph-OSD container, the OSD store type will be handled when start the Ceph OSD container. If any one label of block, block.wal or block.db is defined, activate the Ceph OSD according to the configuration. If there is no label associated with block.wal and block.db, then activate Ceph OSD in one docker volume.

Indicate block, block.wal and block.db belonging to the same Ceph OSD according to the partition labels, it keeps the same method used in Kolla Ceph filestore. * KOLLA_CEPH_OSD_BOOSTRAP_BS_xxx is the block volume label of one bluestore OSD * KOLLA_CEPH_OSD_BOOSTRAP_BS_xxx_W is the block.wal volume label of one bluestore OSD * KOLLA_CEPH_OSD_BOOSTRAP_BS_xxx_D is the block.db volume label of one bluestore OSD Here, xxx is the suffix used to indicate the above volumes belong to the same Ceph OSD.

Security Impact

There is no security impact introduced.

Performance Impact

There is no performance imapct introduced.

Implementation

Assignee(s)

Tone Zhang (tone_zrt)

Milestones

Target Milestone for completion: Rocky

Work Items

  1. Expose OSD store type in Kolla configuration file

2. Check disk partition labels when start Ceph-OSD container if the store type is bluestore 3. Modify the Ceph-OSD starting script to support bluestore 4. Active block, block.wal and block.db configurable in Ceph bluestore OSD

Testing

The existing gate checks will be used to ensure Ceph bluestore OSD successful deployment.

Documentation Impact

The reference page Ceph in Kolla [2] should be updated. The page will document how to change the Ceph store type and how to deploy Ceph bluestore OSD.

References

[1] http://docs.ceph.com/docs/master/ [2] https://docs.openstack.org/kolla-ansible/latest/reference/ceph-guide.html