restore borg prefixes

group_vars/matrix_servers

@@ -1881,6 +1881,8 @@ matrix_bot_draupnir_systemd_required_services_list: |
 backup_borg_enabled: false
 
 backup_borg_identifier: matrix-backup-borg
+backup_borg_retention_prefix: matrix-
+backup_borg_storage_archive_name_format: matrix-{now:%Y-%m-%d-%H%M%S}
 
 backup_borg_base_path: "{{ matrix_base_data_path }}/backup-borg"