Glossary

Backend — how restic reaches the repository's storage: local path, SFTP, REST server, or object storage. Chapter 11.

Blob — one stored, encrypted chunk inside a pack. Chapter 2.

Cache — restic's local scratch copy of repository indexes, for speed. Always safe to delete; it rebuilds.

Check — restic check: verifies repository structure; with --read-data, decrypts and hash-verifies the data itself. Chapter 10.

Chunk — a piece of a file, cut at a content-chosen boundary, named by its hash. Identical chunks are stored once. Chapter 2.

Deduplication — storing each distinct chunk once, however many files or snapshots point at it. Chapter 6.

Forget — removing snapshots by a retention policy. Frees nothing by itself; see prune. Chapter 9.

Key — a wrapped copy of the master key, opened by one password. A repository can hold several. Chapter 2.

Lock — a marker that a restic process is working in a repository; blocks other writers. Stale locks are removed with restic unlock. Chapter 15.

Master key — the random key that actually encrypts the data, generated at init and never typed by anyone. Chapter 2.

Pack — the file on disk that bundles many blobs together; the unit prune rewrites. Chapter 2.

Parent snapshot — the previous snapshot of the same paths on the same host, used to recognise unchanged files without re-reading them. Chapter 5.

Prune — sweeping blobs no snapshot references and repacking packs without them. Chapter 9.

Repository — the store restic manages: config, keys, data, index, snapshots, locks. One folder, never edited by hand. Chapter 4.

Rest-server — the companion program that serves repositories over HTTP, optionally append-only. Chapter 11.

Snapshot — one complete, browsable picture of the backed-up paths at a moment, physically sharing chunks with its neighbours. Chapters 1 and 6.

Tag — a free-text label on a snapshot, used by filters and retention policies. Chapter 5.

Tree — a snapshot's directory listing, where each entry points at the chunks that rebuild a file. Chapter 2.