btrbk/doc/btrbk.1

.TH "btrbk" "1" "2015-03-02" "btrbk v0.11" ""
.SH NAME
btrbk \- backup tool for btrfs volumes
.SH SYNOPSIS
\fBbtrbk\fR [\-\-version] [\-\-help] [\-c <file>] [\-p] [\-v] [\-q] [\-l <level>] <command> [<args>]
.SH DESCRIPTION
\fBbtrbk\fR 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.
.PP
Snapshots as well as backup subvolume names are created in form:
.IP
<source_name>.YYYYMMDD[_N]
.PP
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.
.SH OPTIONS
.TP
\-\-version
Prints the btrbk version.
.TP
\-\-help
Prints the synopsis and a list of the commands.
.TP
\-c <file>
Read the configuration from <file>.
.TP
\-p
Preserve all backups. Skips deletion of old backups, even if specified
in the configuration file.
.TP
\-v
Verbose output. Identical to: \-l info.
.TP
\-q
Quiet operation. If set, btrbk does not print the summary after
executing the "run" command.
.TP
\-l <level>
Set the level of verbosity. Accepted levels are warn, info, debug,
and trace.
.SH COMMANDS
.PP
.B run
[subvolume...]
.RS 4
Perform backup operations as specified in the configuration file. If
the optional [subvolume...] arguments are present, backups are only
performed for the specified subvolumes (which must match a
volume/subvolume declaration in the configuration file), and the -p
(preserve backups) option is implied.
.PP
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.
.PP
If the checks succeed, btrbk creates snapshots for all the source
subvolumes specified in the configuration file.
.PP
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.
.PP
In a last step, previous snapshots and backup subvolumes that are not
preserved by the current retention policy will be deleted. This step
will be skipped if the -p (preserve backups) option is present.
.RE
.PP
.B dryrun
[subvolume...]
.RS 4
Don't run btrfs commands, just show the snapshots and backup
subvolumes that what would be created/deleted by the \fBrun\fR
command. Use in conjunction with \fI\-l debug\fR to see the btrfs
commands that would be executed.
.RE
.PP
.B info
.RS 4
Print filesystem usage information for all source/target volumes.
.RE
.PP
.B tree
.RS 4
Print the snapshots and their corresponding backup subvolumes as a
tree.
.RE
.PP
.B origin
<subvolume>
.RS 4
Print origin information for the given backup subvolume, showing the
parent-child relationship as well as the received-from information.
.RE
.PP
.B diff
<from> <to>
.RS 4
Print new files since subvolume <from> for subvolume <to>.
.RE
.SH FILES
.TP
/etc/btrbk.conf
.PD 0
.TP
/etc/btrbk/btrbk.conf
Default configuration file. The file format and configuration options
are described in
.BR btrbk.conf (5).
.PD
.SH EXIT STATUS
.sp
\fBbtrbk\fR returns a zero exit status if it succeeds. Non zero is
returned in case of failure.
.SH AVAILABILITY
Please refer to the btrbk project page
\fBhttp://www.digint.ch/btrbk\fR for further
details.
.SH SEE ALSO
.BR btrbk.conf (5),
.BR btrfs (1)
.PP
For more information about btrfs and incremental backups, see the web
site at https://btrfs.wiki.kernel.org/index.php/Incremental_Backup
.SH AUTHOR
Axel Burri <axel@tty0.ch>