Hello There!
I thought I’d share a backup script that was written to consolidate backups onto one server instead of spreading the backup process across several servers. The advantages are somewhat obvious to consolidating the script onto one server, namely being that editing or making changes is much easier as you only have one script to edit.
The environment where this may be ideal would be for environments with 15-20 servers or less. I’d recommend a complete end-to-end backup solution for servers that exceed that number such as Bacula perhaps.
The bash shell script that I pasted below is very straightforward and takes two arguments. The first is the hostname or ip address of the destination server you are backing up. The next (and potentially unlimited) arguments will be single quote encased folders which you would want backed up.
This script is dependent on the server the script is running on having ssh key based authentication enabled and implemented for the root user. Security considerations can be made with IP based restrictions either in the ssh configuration, firewall configuration or other considerations.
#!/bin/sh
# Offsite Backup script
# Written by www.stardothosting.com
# Dynamic backup script
currentmonth=`date "+%Y-%m-%d %H:%M:%S"`
currentdate=`date "+%Y-%m-%d%H_%M_%S"`
backup_email="backups@youremail.com"
backupserver="origin-backup-server.hostname.com"
# Check User Input
if [ "$#" -lt 2 ]
then
echo -e "nnUsage Syntax :"
echo -e "./backup.sh [hostname] [folder1] [folder2] [folder3]"
echo -e "Example : ./backup.sh your-server.com '/etc' '/usr/local/www' '/var/lib/mysql'nn"
exit 1
fi
# get the server's hostname
host_name=`ssh -l root $1 "hostname"`
echo "Host name : $host_name"
if [ "$host_name" == "" ]
then
host_name="unknown_$currentdate"
fi
echo "$host_name Offsite Backup Report: " $currentmonth > /var/log/backup.log
echo -e "----------------------------------------------------------" >> /var/log/backup.log
echo -e "" >> /var/log/backup.log
# Ensure permissions are correct
chown -R backups:backups /home/fileserver/backups/
ls -d /home/fileserver/backups/* | grep -v ".ssh|.bash" | xargs -d "n" chmod -R 775
# iterate over user arguments & set error level to 0
errors=0
for arg in "${@:2}"
do
# check if receiving directory exists
if [ ! -d "/home/fileserver/backups/$host_name" ]
then
mkdir /home/fileserver/backups/$host_name
fi
sanitize=`echo $arg | sed 's/[^/]/+$ //'`
sanitize_dir=`echo $arg | awk -F '/' '{printf "%s", $2}'`
/usr/bin/ssh -o ServerAliveInterval=1 -o TCPKeepAlive=yes -l root $1 "/usr/bin/rsync -ravzp --progress --exclude 'clam_quarantinedir' $sanitize/ backups@$backupserver:/home/fileserver/backups/$host_name/$sanitize_dir; echo $? > /tmp/bu_rlevel.txt" >> /var/log/backup.log 2>&1
echo "/usr/bin/ssh -o ServerAliveInterval=1 -o TCPKeepAlive=yes -l root $1 "/usr/bin/rsync -ravzp --progress --exclude 'clam_quarantinedir' $sanitize/ backups@$backupserver:/home/fileserver/backups/$host_name/$sanitize_dir""
runlevel=`ssh -l root $1 "cat /tmp/bu_rlevel.txt"`
echo "Runlevel : $runlevel"
if [ "$runlevel" -ge 1 ]
then
errors=$((counter+1))
else
echo -e "Script Backup for $arg Completed Successfully!" >> /var/log/backup.log 2>&1
fi
done
# Check error level
if [ $errors -ge 1 ]
then
echo -e "There were some errors in the backup job for $host_name, please investigate" >> /var/log/backup.log 2>&1
cat /var/log/backup.log | mail -s "$host_name Backup Job failed" $backup_email
else
cat /var/log/backup.log | mail -s "$host_name Backup Job Completed" $backup_email
fi
It should be explained further that this script actually connects to the destination server as the root user, using ssh key authentication. It then initiates a remote rsync command on the destination server back to the backup server as a user called “backupuser”. So that means that not only does the ssh key need to be installed for root on the destination servers, but a user called “backupuser” needs to be added on the backup server itself, with the ssh keys of all the destination servers installed for the remote rsync.
Hopefully I did not over complicate this, because it really is quite simple :
Backup Server –> root –> destination server to backup — > backupuser rsync –> Backup Server
Once you implement the script and do a few dry run tests then it might be ready to implement a scheduled task for each destination server. Here is an example of one cron entry for a server to be backed up :
01 1 * * * /bin/sh /usr/local/bin/backups.sh destination-server-hostname '/etc' '/usr/local/www' '/home/automysql-backups'
