Ceph Cheatsheet - Ceph Commands & Status Overview - databases Cheatsheets

Ceph Cluster Status Overview

Quickly check the overall health and status of your Ceph cluster with the following command:

$ ceph -s
  cluster:
    id:     uuid-x-x-x-x
    health: HEALTH_OK

  services:
    mon: 1 daemons, quorum ceph:10.20.30.40:16789
    mgr: 1f2c207d5ec9(active)
    osd: 3 osds: 3 up, 3 in

  data:
    pools:   2 pools, 200 pgs
    objects: 16  objects, 21 MiB
    usage:   3.0 GiB used, 27 GiB / 30 GiB avail
    pgs:     200 active+clean

Managing Ceph Pools

List all available pools in your Ceph cluster:

$ ceph osd lspools
1 default
2 volumes

List objects within a specific pool (e.g., 'volumes'):

$ rados -p volumes ls
rbd_header.10516b8b4567
journal_data.2.10516b8b4567.1
journal_data.2.10516b8b4567.2

View disk space utilization for a particular pool:

$ rados df -p volumes
POOL_NAME   USED OBJECTS CLONES COPIES MISSING_ON_PRIMARY UNFOUND DEGRADED RD_OPS     RD WR_OPS     WR
volumes   21 MiB      16      0     48                  0       0        0    665 11 MiB    794 16 MiB

total_objects    16
total_used       3.0 GiB
total_avail      27 GiB
total_space      30 GiB

Retrieving Pool PG Number

Get the current number of Placement Groups (PGs) for a specific pool:

$ ceph osd pool get volumes pg_num
pg_num: 100

Configuring Ceph Dashboard Credentials

Set or update the username and password for accessing the Ceph Dashboard:

ceph dashboard set-login-credentials

Ceph Docker Integration Dockerized Ceph Projects:

Ceph OSD Docker: A repository for running Ceph OSDs within Docker containers.

Docker Volume Plugin for Ceph:

Cepher: A Docker volume plugin that allows Docker to use Ceph storage.

Additional Ceph Resources

Ceph Dashboard Documentation: Official documentation for the Ceph Dashboard.
Ceph FAQ, Tweaks, and Howtos: Community-contributed tips and guides for Ceph.