snapshot-exception-store · shipping · also dm-snapshot exception store

Snapshot exception store

A snapshot exception store records changed-chunk mappings used to reconstruct a classic device-mapper snapshot.

Related Observatory article: Snapshot exception store on hesela.com

The snapshot reads unchanged chunks from its origin and changed chunks from its copy-on-write device. The exception metadata identifies that correspondence. The COW device is therefore not a standalone full-volume image. [1]

Persistent stores retain the metadata across reboots; transient stores do not. [1]

Relations

related
Storage snapshot, Snapshot merge (LVM), Copy-on-write (storage), LVM, Volume manager

Citations

  1. Linux device-mapper: snapshot targets and merge completion (accessed 2026-10-22)
Sources & caveats
  • Scope: classic Linux dm-snapshot, not dm-thin, filesystem snapshots or exception handling in a programming language.

JSON: /data/terms/snapshot-exception-store.json

Published by Hesela team · Updated

Report a correction · Editorial standards · Reuse guidance

Cite this page
Hesela team. Snapshot exception store. Hesela. 2026-10-22. https://hesela.dev/terms/snapshot-exception-store/