commit 9e5ea25c51abbb83d8a0a6d23f5a29eae5125da7
parent 9badac0cb832a6bc133c22a7b617f39dce635a09
Author: vaplv <vaplv@posteo.net>
Date: Sun, 1 Oct 2023 18:42:10 +0200
Write backup man page
Diffstat:
| M | Makefile | | | 3 | +++ |
| A | backup.8 | | | 88 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
2 files changed, 91 insertions(+), 0 deletions(-)
diff --git a/Makefile b/Makefile
@@ -20,7 +20,10 @@ default:
lint:
shellcheck -o all backup
+ mandoc -T lint backup.8
install:
mkdir -p $(DESTDIR)$(PREFIX)/bin
+ mkdir -p $(DESTDIR)$(PREFIX)/share/man/man8/
cp backup $(DESTDIR)$(PREFIX)/bin
+ cp backup.8 $(DESTDIR)$(PREFIX)/share/man/man8/
diff --git a/backup.8 b/backup.8
@@ -0,0 +1,88 @@
+.\" Copyright (C) 2023 vaplv (vaplv@posteo.net)
+.\"
+.\" This program is free software: you can redistribute it and/or modify
+.\" it under the terms of the GNU General Public License as published by
+.\" the Free Software Foundation, either version 3 of the License, or
+.\" (at your option) any later version.
+.\"
+.\" This program is distributed in the hope that it will be useful,
+.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
+.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+.\" GNU General Public License for more details.
+.\"
+.\" You should have received a copy of the GNU General Public License
+.\" along with this program. If not, see <http://www.gnu.org/licenses/>.
+.Dd October 1, 2023
+.Dt BACKUP 8
+.Os
+.Sh NAME
+.Nm backup
+.Nd filesystem backup
+.Sh SYNOPSIS
+.Nm
+.Pa backup_dir
+.Pa files_to_backup ...
+.Sh DESCRIPTION
+.Nm
+backups the files listed in the
+.Pa files_to_backup
+arguments to the
+.Pa backup_dir
+directory.
+It is a shell script that relies on the
+.Xr dump 8
+utility to provide an incremental backup strategy based on the Tower of
+Hanoi sequence.
+.Pp
+A complete backup cycle is built around 3 consecutive Tower of Hanoi
+sequences.
+The first sequence begins with a full backup
+.Pq level 0 .
+The other two sequences begin with an incremental backup of level 1.
+This is the only level that will have several files
+.Pq in this case 2
+during a complete backup cycle.
+.Pp
+The dump levels of a complete backup cycle are as follows:
+.Bd -literal -offset Ds
+0 -> 3 -> 2 -> 5 -> 4 -> 7 -> 6 -> 9 -> 8
+1a -> 3 -> 2 -> 5 -> 4 -> 7 -> 6 -> 9 -> 8
+1b -> 3 -> 2 -> 5 -> 4 -> 7 -> 6 -> 9 -> 8 -> 0
+.Ed
+.Pp
+The identifiers used to define the next backup file are stored in the
+file defined by the
+.Ev NEXTBACKUP
+environment variable.
+The dump level between
+.Bq 0, 9
+is listed first, followed by a space and the index of the Hanoi Tower
+sequence number
+.Pq between Bq 0, 2 .
+.Sh ENVIRONMENT
+.Bl -tag -width Ds
+.It Ev NEXTBACKUP
+File in which identifiers for the next backup file are stored.
+Default is
+.Pa /etc/nextbackup .
+.El
+.Sh EXIT STATUS
+.Ex -std
+.Sh EXAMPLES
+Daily backup of partition
+.Pa /dev/sda3
+in
+.Pa /mnt/storage .
+Note that in this example, backups are performed manually, but that
+.Xr cron 8
+could be used to automate the process:
+.Bd -literal -offset Ds
+backup /mnt/storage /dev/sda3 # Day 1 -> Level 0
+backup /mnt/storage /dev/sda3 # Day 2 -> level 3
+backup /mnt/storage /dev/sda3 # Day 3 -> level 2
+backup /mnt/storage /dev/sda3 # Day 4 -> level 5
+\&...
+.Ed
+.Sh SEE ALSO
+.Xr cron 8 ,
+.Xr dump 8
