Overview

Ceph follows a major release cadence with named versions - Quincy, Reef, Squid, and so on. Each release brings new features, performance improvements, and changes that affect Rook deployments. Knowing how to evaluate these is essential for planning upgrades.

Where to Find Release Notes

The primary sources for Ceph release information are:

# View release notes for currently running version
kubectl -n rook-ceph exec -it deploy/rook-ceph-tools -- ceph version
# Then check: https://docs.ceph.com/en/latest/releases/

Official channels to track:

• Ceph release notes at docs.ceph.com/en/latest/releases/
• Rook release notes at rook.io/docs/rook/latest/
• Ceph blog at ceph.io/en/news/

Evaluating Features by Component

RADOS / Core Storage

New RADOS features often affect data durability and performance:

# Check current RADOS features enabled in pools
kubectl -n rook-ceph exec -it deploy/rook-ceph-tools -- ceph osd pool get mypool all | grep pg_num
kubectl -n rook-ceph exec -it deploy/rook-ceph-tools -- ceph features

RBD (Block Storage)

View enabled RBD features on an image to evaluate snapshot and clone capabilities:

kubectl -n rook-ceph exec -it deploy/rook-ceph-tools -- rbd info mypool/myimage

Enable a new RBD feature on existing images:

kubectl -n rook-ceph exec -it deploy/rook-ceph-tools -- rbd feature enable mypool/myimage deep-flatten

CephFS

Track new MDS features with each release:

kubectl -n rook-ceph exec -it deploy/rook-ceph-tools -- ceph fs dump
kubectl -n rook-ceph exec -it deploy/rook-ceph-tools -- ceph mds stat

RGW (Object Storage)

Review RGW zone configuration and enabled features:

kubectl -n rook-ceph exec -it deploy/rook-ceph-tools -- radosgw-admin zone get

Rook-Specific Feature Gates

Rook exposes new Ceph features through the CephCluster spec. For example, to set the Ceph version and enable modules:

apiVersion: ceph.rook.io/v1
kind: CephCluster
spec:
  cephVersion:
    image: quay.io/ceph/ceph:v19.2.0
  mgr:
    modules:
      - name: pg_autoscaler
        enabled: true

Check the current CephCluster configuration:

kubectl -n rook-ceph get cephcluster rook-ceph -o jsonpath='{.spec.mgr.modules}'

Tracking the Changelog Programmatically

Script to compare features between two releases:

#!/bin/bash
PREV_VER="18.2.0"
NEW_VER="19.2.0"
echo "Comparing Ceph $PREV_VER vs $NEW_VER"
curl -s "https://raw.githubusercontent.com/ceph/ceph/v${NEW_VER}/doc/releases/squid.rst" | head -100

Summary

Tracking new Ceph features requires consulting official release notes, the Rook changelog, and using ceph CLI commands to inspect enabled features. By systematically reviewing each component - RADOS, RBD, CephFS, and RGW - you can identify high-value features to enable and plan informed upgrades for your Rook-managed cluster.