DOKK / manpages / debian 12 / borgbackup2 / borg2-mount.1.en
BORG-MOUNT(1) borg backup tool BORG-MOUNT(1)

borg-mount - Mount archive or an entire repository as a FUSE filesystem

borg [common options] mount [options] MOUNTPOINT [PATH...]

This command mounts an archive as a FUSE filesystem. This can be useful for browsing an archive or restoring individual files. When restoring, take into account that the current FUSE implementation does not support special fs flags and ACLs.

Unless the --foreground option is given the command will run in the background until the filesystem is umounted.

The command borgfs provides a wrapper for borg mount. This can also be used in fstab entries: /path/to/repo /mnt/point fuse.borgfs defaults,noauto 0 0

To allow a regular user to use fstab entries, add the user option: /path/to/repo /mnt/point fuse.borgfs defaults,noauto,user 0 0

For FUSE configuration and mount options, see the mount.fuse(8) manual page.

Borg's default behavior is to use the archived user and group names of each file and map them to the system's respective user and group ids. Alternatively, using numeric-ids will instead use the archived user and group ids without any mapping.

The uid and gid mount options (implemented by Borg) can be used to override the user and group ids of all files (i.e., borg mount -o uid=1000,gid=1000).

The man page references user_id and group_id mount options (implemented by fuse) which specify the user and group id of the mount owner (aka, the user who does the mounting). It is set automatically by libfuse (or the filesystem if libfuse is not used). However, you should not specify these manually. Unlike the uid and gid mount options which affect all files, user_id and group_id affect the user and group id of the mounted (base) directory.

Additional mount options supported by borg:

  • versions: when used with a repository mount, this gives a merged, versioned view of the files in the archives. EXPERIMENTAL, layout may change in future.
  • allow_damaged_files: by default damaged files (where missing chunks were replaced with runs of zeros by borg check --repair) are not readable and return EIO (I/O error). Set this option to read such files.
  • ignore_permissions: for security reasons the "default_permissions" mount option is internally enforced by borg. "ignore_permissions" can be given to not enforce "default_permissions".

The BORG_MOUNT_DATA_CACHE_ENTRIES environment variable is meant for advanced users to tweak the performance. It sets the number of cached data chunks; additional memory usage can be up to ~8 MiB times this number. The default is the number of CPU cores.

When the daemonized process receives a signal or crashes, it does not unmount. Unmounting in these cases could cause an active rsync or similar process to delete data unintentionally.

When running in the foreground ^C/SIGINT unmounts cleanly, but other signals or crashes do not.

See borg-common(1) for common options of Borg commands.

where to mount filesystem
paths to extract; patterns are supported

Show checkpoint archives in the repository contents list (default: hidden).
stay in foreground, do not daemonize
Extra mount options
use numeric user and group identifiers from archive(s)

only consider archive names matching the pattern. see "borg help match-archives".
Comma-separated list of sorting keys; valid keys are: timestamp, name, id; default is: timestamp
consider first N archives after other filters were applied
consider last N archives after other filters were applied
consider archives between the oldest archive's timestamp and (oldest + TIMESPAN), e.g. 7d or 12m.
consider archives between the newest archive's timestamp and (newest - TIMESPAN), e.g. 7d or 12m.
consider archives older than (now - TIMESPAN), e.g. 7d oder 12m.
consider archives newer than (now - TIMESPAN), e.g. 7d or 12m.

exclude paths matching PATTERN
read exclude patterns from EXCLUDEFILE, one per line
include/exclude paths matching PATTERN
read include/exclude patterns from PATTERNFILE, one per line
Remove the specified number of leading path elements. Paths with fewer elements will be silently skipped.

borg-common(1), borg-umount(1), borg-extract(1)

The Borg Collective

2023-03-01