CephFSStaleSubvolume

A subvolume in a Ceph filesystem becomes stale when it loses connection to its associated PersistentVolume. This results in orphaned data that consumes storage space but remains inaccessible to the user. This alert is triggered when stale subvolumes exist in a Ceph filesystem.

Impact: High

Diagnosis

To identify stale subvolumes in the filesystem, you need to use the ODF CLI tool.

  1. Install ODF CLI

    If not already installed, follow the installation instructions at: Using the ODF CLI command.

  2. List all subvolumes including those marked as stale: 
    odf subvolume ls
  3. List only the stale subvolumes: 
    odf subvolume ls --stale

Mitigation

If the stale subvolumes are no longer needed and not currently in use, you can safely delete them to reclaim storage space:

odf subvolume delete <filesystem> <subvolume> <subvolumegroup>

The subvolume, subvolumegroup, and filesystem details can be retrieved using the subvolume list command.