Preview Borg archive recreation before applying exclusion changes

Review historical archive changes and temporary space before running Borg recreation.

Source facts

Borg 1.4.5 recreate can permanently remove files from existing archives according to selected paths and patterns. Its documentation recommends combining dry-run, verbose output, and listing to inspect how those selections are interpreted. During actual recreation, a new archive exists alongside the original until completion, and its archive identifier changes. Using a separate target preserves the original instead of replacing it. Rechunking or recompression can also require substantial extra space while old and new representations coexist.

Source: Borg 1.4.5 — borg recreate.

Applicability

This applies to Borg 1.4.5 archive recreation. It addresses modifying historical backup content, not the ordinary inclusion rules for creating a new backup or an automatic privacy-erasure guarantee.

DSE recommendation

DSE recommends reviewing the exact archive selection and file list before approving recreation. State whether the task is removing an accidental inclusion, changing compression, or changing chunking, and preserve a suitable recovery copy under the applicable policy. Prefer a separately named target during the rehearsal so reviewers can compare content. Check temporary capacity and downstream references to archive identifiers. Do not let a broad pattern silently change a wider historical set than the request intended.

Verification

Run the selection preview on disposable archives and review every planned omission. Recreate to a separate target, compare restored representative files, and confirm only intended content differs. Retain the original and new identifiers, selected patterns, capacity observations, and the explicit decision about eventual original-archive disposal.

Official reference

Borg 1.4.5 — borg recreate. Reviewed October 15, 2026.