Why is Delete unavailable for an immutable Synology snapshot?

Applies to: Snapshot Replication on compatible Synology systems with immutable-snapshot support.

Work through these checks

1. Open Snapshot Replication and select the correct shared folder or LUN. In Snapshot > Snapshot List, inspect the shield indicator or snapshot details to see the remaining protection period.
2. Check the selected items individually. Including an immutable snapshot in a multiple selection can disable deletion for that selection. Also check whether replication is preserving a latest synchronised snapshot.
3. Review capacity and future snapshot schedules with the data owner. Reduce unnecessary future growth or plan supported capacity expansion while preserving recovery objectives. Changing future retention does not cancel an existing immutable protection period.
4. After protection expires, review which recovery points are still required before removing eligible snapshots through the normal interface. Space still referenced by other snapshots or recycle bins may remain allocated.

Confirm the result

The protection expiry and retention policy explain the unavailable control. After any approved cleanup, verify retained snapshots can still be browsed and restored.

If you need help

Include these details in your ticket: Model, DSM/Snapshot Replication versions, protection expiry and redacted capacity and snapshot-list screens.

Updated 261107