X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~mdw/git/rsync-backup/blobdiff_plain/69305044e24a190f8d1e994c548d743d500c4f39..977d0da99bb1ccfdbdcbccbb0fd059662c30737b:/rsync-backup.8?ds=sidebyside

diff --git a/rsync-backup.8 b/rsync-backup.8
index a32c656..e8276e4 100644
--- a/rsync-backup.8
+++ b/rsync-backup.8
@@ -5,9 +5,11 @@
 \h'-\w'\fB\\$1\ \fP'u'\fB\\$1\ \fP\c
 ..
 .TH rsync-backup 8 "7 October 2012" rsync-backup
+.SH NAME
+rsync-backup \- back up files using rsync
 .SH SYNOPSIS
 .B rsync-backup
-.RB [ \-v ]
+.RB [ \-nv ]
 .RB [ \-c
 .IR config-file ]
 .SH DESCRIPTION
@@ -73,6 +75,10 @@ in the
 .B \-V
 output).
 .TP
+.B \-n
+Don't actually take a backup, or write proper logs: instead, write a
+description of what would be done to standard error.
+.TP
 .B \-v
 Produce verbose progress information on standard output while the backup
 is running.  This keeps one amused while running a backup
@@ -152,7 +158,10 @@ will avoid inefficient and pointless messing about
 in this case.
 This command clears the
 .B like
-list.
+list, and resets the retention policy to its default (i.e., the to
+policy defined prior to the first
+.B host
+command).
 .TP
 .BI "like " "host\fR ..."
 Declare that subsequent filesystems are `similar' to like-named
@@ -193,12 +202,53 @@ or
 Expiry considers each existing dump against the policy lines in order:
 the last applicable line determines the dump's fate \(en so you should
 probably write the lines in decreasing order of duration.
+.PP
+Groups of
+.B retain
+commands between
+.B host
+and/or
+.B backup
+commands collectively define a retention policy.  Once a policy is
+defined, subsequent
+.B backup
+operations use the policy.  The first
+.B retain
+command after a
+.B host
+or
+.B backup
+command clears the policy and starts defining a new one.  The policy
+defined before the first
+.B host
+is the
+.I default
+policy: at the start of each
+.B host
+stanza, the policy is reset to the default.
+.TP
+.BI "retry " count
+The
+.B live
+snapshot type (see below) doesn't prevent a filesystem from being
+modified while it's being backed up.  If this happens, the
+.B fshash
+pass will detect the difference and fail.  If the filesystem in question
+is relatively quiescent, then maybe retrying the backup will result in a
+successful consistent copy.  Following this command, a backup which
+results in an
+.B fshash
+mismatch will be retried up to
+.I count
+times before being declared a failure.
 .TP
 .BI "snap " type " " \fR[\fIargs\fR...]
 Use the snapshot
 .I type
 for subsequent backups.  Some snapshot types require additional
-arguments, which may be supplied here.
+arguments, which may be supplied here.  This command clears the
+.B retry
+counter.
 .SS Configuration variables
 The following shell variables may be overridden by the configuration
 file.
@@ -364,6 +414,10 @@ Backup trees are stored in a fairly straightforward directory tree.
 At the top level is one directory for each client host.  There are also
 some special entries:
 .TP
+.B \&.rsync-backup-store
+This file must be present in order to indicate that a backup volume is
+present (and not just an empty mount point).
+.TP
 .B fshash.cache
 The cache database used for improving performance of local file
 hashing.  There may be other