NAME
btrbk − backup tool for btrfs volumes
SYNOPSIS
btrbk [−−version] [−−help] [−c <file>] [−v] [−q] [−l <level>] <command> [<args>]
DESCRIPTION
btrbk is a backup tool for btrfs subvolumes, taking advantage of btrfs specific capabilities to create atomic snapshots and transfer them incrementally to target volumes. It is able to perform backups from one source to multiple destinations.
Snapshots as well as backup subvolume names are created in form:
<source_name>.YYYYMMDD[_N]
Where YYYY is the year, MM is the month, and DD is the day of creation, and, if multiple backups are created on the same day, N will be incremented on each backup, starting at 1.
OPTIONS
−−version
Prints the btrbk version.
−−help
Prints the synopsis and a list of the commands.
−c <file>
Read the configuration from <file>.
−v
Verbose output. Identical to: −l info.
−q
Quiet operation. If set, btrbk does not print the summary
after executing the "run" command.
−l <level>
Set the level of verbosity. Accepted levels are warn, info,
debug, and trace.
COMMANDS
run
Perform backup operations as specified in the configuration file:
First, btrbk reads information from the source/target btrfs volumes in order to do sanity checks and find out about parent/child as well as received-from relationships.
If the checks succeed, btrbk creates snapshots for all the source subvolumes specified in the configuration file.
Then, for each specified target, btrbk creates a new backup subvolume, incremental from the latest common snapshot / backup subvolume found. If no common parent subvolume is found, a full backup is created.
In a last step, previous snapshots and backup subvolumes that are not preserved by the current retention policy will be deleted.
dryrun
Don’t run btrfs commands, just show the snapshots and backup subvolumes that what would be created/deleted by the run command. Use in conjunction with −l debug to see the btrfs commands that would be executed.
info
Print filesystem usage information for all source/target volumes.
tree
Print the snapshots and their corresponding backup subvolumes as a tree.
origin <subvolume>
Print origin information for the given backup subvolume, showing the parent-child relationship as well as the received-from information.
diff <from> <to>
Print new files since subvolume <from> for subvolume <to>.
FILES
/etc/btrbk.conf
/etc/btrbk/btrbk.conf
Default configuration file. The file format and configuration options are described in btrbk.conf(5).
EXIT STATUS
btrbk returns a zero exit status if it succeeds. Non zero is returned in case of failure.
AVAILABILITY
Please refer to the btrbk project page http://www.digint.ch/btrbk for further details.
SEE ALSO
btrbk.conf(5), btrfs(1)
For more information about btrfs and incremental backups, see the web site at https://btrfs.wiki.kernel.org/index.php/Incremental_Backup
AUTHOR
Axel Burri <axel@tty0.ch>