RSYNC BACKUP MADE EASY
Using rsync for backups is becoming more and more popular on UNIX/Linux systems. Especially the variant with hardlinks on the backup media to conserve disk space has proven itself to be a very reliable backup solution. The method is already widely published on the Internet (e.g. this is a nice introduction), so that I will save myself the trouble of repeating it.
In a nutshell you get perpetual incremental backups that appear as full backups (for each day) and thus allow easy restore or further copying to tape etc. After the initial full backup RBME will forever do incremental backups against the last backup to conserve time and network bandwidth.
RBME is a simple tool to assist in implementing a general backup solution based on rsync and hardlinks with an automated management of the disk space on the backup media. This is achieved by removing old backups from the backup media in a way which will ensure that (over the long run) the amount of backups should even out for all hosts involved.
This is also the major reason for me to write this script, I didn't find a suitable script (that would manage the backup space and also watch the inodes) when I needed it. The other reason is of course the fact that studying another script would take at least the same time as writing my own and in such cases I tend to write my own.
RBME expects you to provide a (large) backup space, preferably on a filesystem of its own (it makes the disk space management easier). After configuring RBME with your backup path and the thresholds that seem appropriate for your environment, simply run rbme for each backup host. By default it will use rsync over ssh to copy that host to the backup filesystem (Use ssh -c blowfish-cbc to somewhat speed up your backups by choosing a faster cipher, if your security policy allows for that). Example:
This example will simply backup the hosts host3, host2 and host1 to your backup space. Every day on which you run RBME it will produce a new subdirectory in the backup space for that day, so that over time your backup space will look like that:
$BACKUP_PATH/
|-- host3/
| |-- 2007-09-02/
| |-- 2007-09-03/
| |-- 2007-09-05/
| |-- 2007-09-06/
| |-- 2007-09-07/
| |-- 2007-09-08/
| |-- 2007-09-09/
| |-- 2007-09-10/
| -- 2007-09-11/ |-- host2/ | |-- 2007-09-02/ | |-- 2007-09-03/ | |-- 2007-09-05/ | |-- 2007-09-06/ | |-- 2007-09-07/ | |-- 2007-09-08/ | |-- 2007-09-09/ | |-- 2007-09-10/ |-- 2007-09-11/
-- host1/ |-- 2007-09-05/ |-- 2007-09-06/ |-- 2007-09-07/ |-- 2007-09-08/ |-- 2007-09-09/ |-- 2007-09-10/ -- 2007-09-11/
Under each date subdirectory you will find a complete copy of the host from that day. Usually RBME is run from cron on a daily or nightly base to keep all hosts always backed up.
RBME produces a nice report of it's activities that serves as a daily backup report:
RSYNC BACKUP MADE EASY version 1.4 / 2008-05-20 Copyright (C) 2006,2008 Schlomo Schapiro, probusiness Berlin AG Licensed under the GNU General Public License, see http://www.gnu.org/licenses/gpl.html for full text
rbme backing up to /media/backup (30127 MB & 20183270 inodes available) Free disk space requirements: 20000 MB & 100000 inodes before host backup 30000 MB & 200000 inodes after host backup
Backup of 'mars:/' in mars/2008-05-10 against 2008-05-09 Backup runtime was 00:03:28 The backup for mars utilizes 81 MB & 19814 inodes
Backup of 'lucky:/ /home /var /media/nfsroot /media/install/sles10sp1' in lucky/2008-05-10 against 2008-05-09 Backup runtime was 00:59:53 The backup for lucky utilizes 1862 MB & 174457 inodes Removing old backups to free some disk space Oldest backup (from 124): 2007-11-27 Having 28184 MB & 19988997 inodes, deleting /media/backup/lucky/2007-11-27 in 939 seconds. Having 29737 MB & 20161230 inodes, deleting /media/backup/lucky/2007-11-28 in 931 seconds.
Backup of 'gw:/' in gw/2008-05-10 against 2008-05-09 Backup runtime was 00:00:25 The backup for gw utilizes 17 MB & 2174 inodes
Backup of 'web:/' in web/2008-05-10 against 2008-05-09 Backup runtime was 00:02:43 The backup for web utilizes 95 MB & 8552 inodes
Backup of 'mysql:/' in mysql/2008-05-10 against 2008-05-09 Backup runtime was 00:01:14 The backup for mysql utilizes 42 MB & 5436 inodes
Backup of 'mail:/' in mail/2008-05-10 against 2008-05-09 Backup runtime was 00:01:22 The backup for mail utilizes 40 MB & 5859 inodes
Backup of 'po:/' in po/2008-05-10 against 2008-05-09 Backup runtime was 00:05:11 The backup for po utilizes 281 MB & 6951 inodes
Backup targets:
mars:/
lucky:/ /home /var /media/nfsroot /media/install/sles10sp1
gw
web
mysql
mail
poAll 7 targets backed up successfully.
Backup filesystem has now 30819 MB available Backup filesystem has now 20304589 inodes available Total runtime was 01:45:51
See '/var/log/rbme.log.10' for full details.
Thank you for using RSYNC BACKUP MADE EASY
You should use the information about inode requirements to fine-tune the RBME configuration to guarantee sufficient free inodes before the backup starts. The amount of used MB and inodes gives an indication about the change rate of each host as only changed files (or new directories) occupy new inodes. Finally RBME gives a short statistical overview about the amount of old backups kept for each host.
RBME comes with a configuration file in /etc/rbme.conf where you should set your own values for the amount of free space or inodes that RBME should keep on your backup filesystem (hence better to use a dedicated filesystem). You can also set how many backups to always keep, even if it would mean violation the disk space thresholds. This ensures to always keep a minimum amount of old backups.
Specify the hosts and paths to backup as parameters to RBME. Two formats are recognized: host Backup the entire host, crossing over mountpoints. Some typical mountpoints are excluded by default, but make sure that you don't backup data unintentionally (like NFS mounts etc.). 'host:/ /var /boot /home' Backup the specified paths on the remote host (you cannot specify a path with a blank in it here, this is an rsync issue, not RBME). In this mode RBME will not descend into mount points, hence you have to specify all mount points or paths to backup here. This method also safeguards against accidentially backing up temporary NFS mounts etc. and is the recommended way to use RBME.
Excludes are managed locally on each backup host, to keep the information local to the host (and allow a local admin to manage his/her own excludes). Simply create a file /etc/backup-excludes.lst on each host to exclude files and directories. Please refer to the rsync manpage (section INCLUDE/EXCLUDE PATTERN RULES) for full details on the format. A small example will suffice here:
/media/stuff/backup/ /media/scratch/backup/ /media/files/backup/*
This example excludes various other backup directories on a server from this backup. The /* notation makes sure that the directory itself is backed up, but not the content.
To verify the configuration simply run RBME without a parameter:
RSYNC BACKUP MADE EASY version 1.4 / 2008-05-20 Copyright (C) 2006,2007 Schlomo Schapiro, probusiness Berlin AG Licensed under the GNU General Public License, see http://www.gnu.org/licenses/gpl.html for full text
Usage:
/usr/bin/rbme <host:/path> ... host:/path is in rsync notation, see rsync(1) for more information Use host without :/path to specify entire host (with certain defaults excluded).
Include / Exclude files: On each backup host, /etc/backup-excludes.lst can be used to specify local excludes (in rsync notation !) and /etc/backup-includes.lst can be used to specify local includes (though usually one uses only excludes, as the includes do NOT include files not part of the :/path spec !).
Instance support: Create symlinks to the executable to create more instances with dedicated configuration. Each instance will have a dedicated logfile and produce different email reports.
Current configuration: (change settings in /etc/rbme.conf (Master) and /etc/rbme.conf (Instance)) BACKUP_PATH = /media/backup MIN_FREE_BEFORE_HOST_BACKUP = 20000 MIN_INODES_BEFORE_HOST_BACKUP = 100000 MIN_FREE_AFTER_HOST_BACKUP = 30000 MIN_INODES_AFTER_HOST_BACKUP = 200000 MIN_KEEP_OLD_BACKUPS = 5 RSYNC = /usr/bin/rsync RSYNC_RSH = ssh -c blowfish-cbc RSYNC_EXTRA_OPTIONS = VERBOSE = REPORT = yes STATISTICS = yes DEBUG = MAILTO = your@email-address.com MAILFROM = root@your.host.name.com MAILSTYLE = report LOGFILE = /var/log/rbme.log.20
Project homepage: http://www.schapiro.org/schlomo/projects
RBME is distributed as tar.gz archive or as noarch DEB (in the out/ folder), which is the recommended installation method for DEB-based systems. After installing RBME you have to edit /etc/rbme.local.conf to adapt RBME to your environment (at least set the backup path).
Start from doing some test runs with a few hosts to get the feeling for RBME and then you can create a cron job that will run RBME regularly and mail the report back to you.
You can contact me at rbme@schlomo.schapiro.org to send me your feedback, thanks and patches
Schlomo Schapiro