Linux backup and restore with the rdiff-backup tool

Rdiff-backup backs up one directory to another, possibly over a network. The target directory ends up being a copy of the source directory. However, extra reverse diffs are stored in a special subdirectory of that target directory, so you can still recover files lost some time ago.

The idea is to combine the best features of a mirror and an incremental backup. rdiff-backup also preserves subdirectories, hard links, dev files, permissions, uid/gid ownership, modification times, extended attributes, acls, and resource forks.

Also, rdiff-backup can operate bandwidth-efficiently over a pipe, like rsync. Thus, you can securely use rdiff-backup and ssh to back up a hard drive to a remote location, and only the differences will be transmitted.  

Debian & Ubuntu

This utility is included in the software repository, so to install, just run as root:

CentOS & RedHat

In this case, the application is not included in the default software repository, so you need to make use of the EPEL repository:

Preliminaries

In these scripts, the following default values are assumed:

• $TOMCAT_HOME value is "/home/openkm/tomcat-9.0.76"
• OpenKM database is named "okmdb."
• OpenKM database password value is "*secret*".
• OpenKM start & stop service script location is "/etc/init.d/tomcat"

Sample script

The USB disk mount point can be defined in /etc/fstab as:

/dev/sdb1    /mnt/backup    ext4    defaults    0    0

These are the global script sections:

• Global var configuration under the ## BEGIN CONFIG ## section.
• Checking the root user under the # Check root section.
• Deleting older database backups in the # Delete older local database backup  section.
• Mount disk (optional section) under the # Mount disk section.
• Stop the application (optional section) under  # Stop tomcat section.
• Clean logs (optional section) under the # Clean logs section.
• Backup the database to the filesystem under the # Backup database section.
• Backup the repository and database dump to the backup destination under the # Backup and purge old backups section.
• Start the application (optional section) under the # Start tomcat section.
• Show statistics (optional section) under the # Status section.
• Umount disk (optional section) under the # Umount disk section.

Explanation of configuration parameters:

Create a backup script /root/backup.sh

#!/bin/bash
#
## BEGIN CONFIG ##
HOST=$(uname -n)
DATABASE_PASS="*secret*"
OPENKM_DB="okmdb"
OPENKM_HOME="/home/openkm"
TOMCAT_HOME="$OPENKM_HOME/tomcat-9.0.76"
DATABASE_EXP="$OPENKM_HOME/db"
BACKUP_DIR="/mnt/backup"
## END CONFIG ##

# Check root user 
if [ $(id -u) != 0 ]; then echo "You should run this script as root"; exit; fi

# Delete older local database backup  
echo -e "### BEGIN: $(date +"%x %X") ###\n"
rm -rf $DATABASE_EXP
mkdir -p $DATABASE_EXP
 
# Mount disk
if mount | grep "$BACKUP_DIR type" > /dev/null; then
  echo "$BACKUP_DIR already mounted";
else
  mount "$BACKUP_DIR";
  
  if mount | grep "$BACKUP_DIR type" > /dev/null; then
    echo "$BACKUP_DIR mounted";
  else
    echo "$BACKUP_DIR error mounting";
    exit -1;
  fi
fi
 
# Stop Tomcat
/etc/init.d/tomcat stop
 
# Clean logs
#echo "Clean Tomcat temporal files."
#rm -rf $TOMCAT_HOME/logs/*
#rm -rf $TOMCAT_HOME/temp/*
#rm -rf $TOMCAT_HOME/work/Catalina/localhost
 
# Backup database
if [ -n "$DATABASE_PASS" ]; then
  echo "* Backuping MySQL data from $OPENKM_DB..."
  mysqldump -h localhost -u root -p$DATABASE_PASS $OPENKM_DB > $DATABASE_EXP/mysql_$OPENKM_DB.sql
  echo "-------------------------------------";
fi
 
# Backup and purge old backups
rdiff-backup --remove-older-than 30B $BACKUP_DIR/$HOST
rdiff-backup -v 3 --print-statistics --include $OPENKM_HOME --exclude '**' / $BACKUP_DIR/$HOST
 
# Start Tomcat
/etc/init.d/tomcat start
echo -e "\n### END: $(date +"%x %X") ###"
 
# Status
echo "=================================";
rdiff-backup --list-increment-sizes $BACKUP_DIR/$HOST
echo "*********************************";
df -h | grep "$BACKUP_DIR"
echo "=================================";
 
# Umount disk
sync
umount "$BACKUP_DIR"

Increase the backup period

Modify the # Backup and purge old backups section to increase the parameter value:

--remove-older-than 90B

Do a remote backup

Modify the # Backup and purge old backups section.

# Backup and purge old backups
rdiff-backup --remove-older-than 30B backup@server::$BACKUP_DIR/$HOST
rdiff-backup -v 3 --print-statistics --include $FILES --exclude '**' / backup@server::$BACKUP_DIR/$HOST

## BEGIN CONFIG ##
BACKUP_DIR="user@server::/path/to/backup"

# Backup and purge old backups
rdiff-backup --remove-older-than 30B $BACKUP_DIR/$HOST

Do a remote backup to SMB or CIFS

Modify the # Mount disk section.

# Mount disk
if mount | grep "$BACKUP_DIR type" > /dev/null; then
  echo "$BACKUP_DIR already mounted";
else
  echo "Mounting $BACKUP_DIR ...";
  mount -t cifs //REMOTE_SERVER/REMOTE_DIR $BACKUP_DIR -o username=REMOTE_USER,password=REMOTE_PASSWORD,iocharset=utf8,file_mode=0777,dir_mode=0777
  
  if mount | grep "$BACKUP_DIR type" > /dev/null; then
    echo "$BACKUP_DIR mounted";
  else
    echo "Error mounting $BACKUP_DIR.";
    exit -1;
  fi
fi

Do a PostgreSQL backup

Modify the # Backup database section.

# Backup de PostgreSQL
echo "* Backuping PostgreSQL data from $OPENKM_DB..."
su postgres -c "pg_dump $OPENKM_DB" > $DATABASE_EXP/pg_$OPENKM_DB.sql
 
# Databases optimizations
su postgres -c "vacuumdb -a -z" > /dev/null
su postgres -c "reindexdb -a -q" 2> /dev/null

Configure crontab

To install the cron job, run the following:

And add these lines according to your configuration:

MAILTO=nomail@openkm.com
@daily /root/backup.sh | tee /root/logs/backup.$(date +\%Y.\%m.\%d_\%H.\%M.\%S).log

Restoring a backup

You can list the available backups:

Then decide to restore one of the backups, for example, the one made on Sun Aug 28 00:00:13 2012:

Or restore the last backup.

Additional information

• rdiff-backup home page
• rdiff-backup wiki
• Automated backups with rdiff-backup
• Using rdiff-backup for remote backups
• Suppress socket warnings when using rdiff-backup