lustre-hsm-release · shipping · also lfs hsm_release

Lustre HSM release

Lustre HSM release removes a file's local data residency while retaining its filesystem identity and dependence on an archived copy.

Related Observatory article: Lustre HSM release on hesela.com

In the reviewed ordinary release path, valid HSM metadata and ARCHIVED are required, while DIRTY, NORELEASE or LOST reject the flag check. NOARCHIVE is a separate policy flag and does not itself reject that check. Passing this preliminary predicate does not establish complete release success. [2] [5]

The client obtains a release lease and data version. The server rereads HSM metadata and, for a file not already released, rejects a mismatch between the supplied and archived versions. A broken lease also prevents the operation. This is the ordinary path, not the separate PCC-attach branch. [3] [2]

Release eligibility is not proof that backend bytes remain retrievable. Preserve the archive mapping and recovery dependencies, then test the intended restore. Changing state flags is not data repair. [1] [4]

In this pinned server function, a rejected flag predicate and a data-version mismatch both return -EPERM. A missing or broken lease returns -ESTALE, and open-semaphore contention returns -EBUSY. These branches are not a complete command-line error map: an error name alone cannot identify the failed safeguard. [2]

Relations

related

Lustre HSM, Cold archive tier, Backup, Restore test

Citations

1. Lustre v2_17_0: mdt_hsm_state_get and mdt_hsm_state_set (accessed 2026-11-04)
2. Lustre v2_17_0: mdt_hsm_release_allow and ordinary mdt_hsm_release path (accessed 2026-11-04)
3. Lustre v2_17_0: ll_data_version and ll_hsm_release (accessed 2026-11-04)
4. Lustre v2_17_0: archive completion and restore/remove compatibility checks (accessed 2026-11-04)
5. Lustre v2_17_0: enum hsm_states and user/status masks (accessed 2026-11-04)

JSON: /data/terms/lustre-hsm-release.json