documentation: btrbk.1: altered text for "run" action, explaining the resume mechanism in more detail

pull/30/head
Axel Burri 2015-05-20 13:46:09 +02:00
parent d935bfc679
commit 8217da5f03
1 changed files with 15 additions and 10 deletions

View File

@ -53,21 +53,26 @@ volume/subvolume declaration in the configuration file), and the -p
(preserve backups) option is implied.
.PP
First, btrbk reads information from the source and target btrfs
volumes in order to perform sanity checks and identify parent/child
and received-from relationships.
filesystems in order to perform sanity checks and identify
parent/child and 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. This is also done for all missing backups if the
\fIresume_missing\fR option is set.
Then, for each specified target, btrbk creates the backups as follows:
If the \fIresume_missing\fR option is set (the default), btrbk
transfers all missing snapshots needed to satisfy the configured
\fItarget_preserve_{daily,weekly,monthly}\fR retention policy, always
incremental from the latest common parent subvolume found. If no
common parent subvolume is found, a full backup is created for the
first transfer. Note that the latest snapshot (the one created in the
first step) is always transferred, regardless of the retention policy.
.PP
In a last step, previous snapshots and backup subvolumes that are not
preserved by their configured retention policy will be deleted. This
step will be skipped if the -p (preserve backups) option is present.
In a last step, unless the -p (preserve backups) option is set,
snapshots and backup subvolumes that are not preserved by their
configured retention policy will be deleted. Note that the latest
snapshot as well as the latest backup is always preserved, regardless
of the retention policy.
.RE
.PP
.B dryrun