Configuration

The ceph-immutable-object-cache is a daemon for object cache of RADOS objects among Ceph clusters.

Before you begin

A running IBM Storage Ceph cluster.
At least one SSD for the cache.

About this task

Important: To use the ceph-immutable-object-cache daemon, you must be able to connect RADOS clusters.

The daemon promotes the objects to a local directory. These cache objects service the future reads. You can configure the daemon by installing the ceph-immutable-object-cache package.

Procedure

Enable the RBD shared read only parent image cache. Add the following parameters under [client] in the /etc/ceph/ceph.conf file:
Example
```
[root@ceph-host01 ~]# vi /etc/ceph/ceph.conf

[client]
rbd parent cache enabled = true
rbd plugins = parent_cache
```
Restart the cluster.

Install the ceph-immutable-object-cache package:

Example

[root@ceph-host1 ~]# dnf install ceph-immutable-object-cache

Create a unique Ceph user ID, the keyring:

Syntax

ceph auth get-or-create client.ceph-immutable-object-cache.USER_NAME mon profile rbd osd profile rbd-read-only

Example

[root@ceph-host1 ~]# ceph auth get-or-create client.ceph-immutable-object-cache.user mon 'profile rbd' osd 'profile rbd-read-only'

[client.ceph-immutable-object-cache.user]
        key = AQCVPH1gFgHRAhAAp8ExRIsoxQK4QSYSRoVJLw==

Copy this keyring.

In the /etc/ceph directory, create a file and paste the keyring:

Example

[root@ceph-host1 ]# vi /etc/ceph/ceph.client.ceph-immutable-object-cache.user.keyring

[client.ceph-immutable-object-cache.user]
        key = AQCVPH1gFgHRAhAAp8ExRIsoxQK4QSYSRoVJLw

Enable the daemon:

Syntax

systemctl enable ceph-immutable-object-cache@ceph-immutable-object-cache.USER_NAME

Specify the USER_NAME as the daemon instance.

Example

[root@ceph-host1 ~]# systemctl enable ceph-immutable-object-cache@ceph-immutable-object-cache.user

Created symlink /etc/systemd/system/ceph-immutable-object-cache.target.wants/ceph-immutable-object-cache@ceph-immutable-object-cache.user.service → /usr/lib/systemd/system/ceph-immutable-object-cache@.service.

Start the ceph-immutable-object-cache daemon:

Syntax

systemctl start ceph-immutable-object-cache@ceph-immutable-object-cache.USER_NAME

Example

[root@ceph-host1 ~]# systemctl start ceph-immutable-object-cache@ceph-immutable-object-cache.user

Verification: Check the status of the configuration:

Syntax

systemctl status ceph-immutable-object-cache@ceph-immutable-object-cache.USER_NAME

Example

[root@ceph-host1 ~]# systemctl status ceph-immutable-object-cache@ceph-immutable-object-cache.user

● ceph-immutable-object-cache@ceph-immutable-object-cache.user>
  Loaded: loaded (/usr/lib/systemd/system/ceph-immutable-objec>
  Active: active (running) since Mon 2021-04-19 13:49:06 IST; >
Main PID: 85020 (ceph-immutable-)
   Tasks: 15 (limit: 49451)
  Memory: 8.3M
  CGroup: /system.slice/system-ceph\x2dimmutable\x2dobject\x2d>
          └─85020 /usr/bin/ceph-immutable-object-cache -f --cl>