#!/bin/bash
##
## hostlogBackup.sh: perform backup of essential log files. Developed by
Jagbir Singh (contact AT jagbir DOT info)
## You are free to use or distribute it in whatever means but I'll be happy
if you send me a copy of updated one.
##
## create some varibales
yesterDate=`date -d "-1 day" +%d-%b-%g` ## yesterday's date
toDay=`date +%u`;
## day of week in numeric
bakServer="backup-user@server-ip" ## backup server address user@hostname, use
directory name if backup in same host
bakHost="$bakServer:/backup/host/firsthost" ## specify directory where log
files will be copied
bakHostDaily="$bakHost/daily/" ## directory for daily backup files
cd /var/log ## change directory where important log file resides
# compress messages log file
`cp messages messages-log`
`/bin/tar czf messages_$toDay.tgz messages-log`
# compress secure log file
`cp secure secure-log`
`/bin/tar czf secure_$toDay.tgz secure-log`
# compress mysqld log file. comment following 2 lines if you are not using
mysql
`cp mysqld.log mysqld-log`
`/bin/tar czf mysqld_$toDay.tgz mysqld-log`
# compress apache log files. uncomment if your server runs apache service.
#`cp httpd/access_log ./access-log`
#`cp httpd/error_log ./error-log`
#`/bin/tar czf httpd_$toDay.tgz access-log error-log`
#copy all compressed files to backup server, you must set secure
authentication for password less scp, else you have to enter password
`/usr/bin/scp *_$toDay.tgz $bakHostDaily`
#remove all temp files
`rm -f *-log`
`rm -f *_$toDay.tgz`
# Apart from daily, Take a weekly backup on Monday for files which get
rotated on weekly basis.
if [ $toDay == "1" ]; then
# take backup of messages log file
if [ -f messages.1 ]; then
`/bin/tar czf message_$yesterDate.tgz messages.1`
`/usr/bin/scp message_$yesterDate.tgz $bakHost`
`rm -f message_$yesterDate.tgz`
fi
# take backup of secure log file
if [ -f secure.1 ]; then
`/bin/tar czf secure_$yesterDate.tgz secure.1`
`/usr/bin/scp secure_$yesterDate.tgz $bakHost`
`rm -f secure_$yesterDate.tgz`
fi
fi
Again I’m stressing on point that this is a very basic script and doesn’t handle any unforseen
situations like file doesn’t exist or what happens if compression or copying to other server fails
etc. You have to do it yourself.
The point of taking backup on weekly basis is that the file combines week log in a single file
which is easy to retain. Daily backup files here get overwritten but I want to retain weekly files
for longer duration.
Now you should run this script on daily basis through cron at around 4:30am. why 4:30? because
the syslog service normally runs at 4:03am daily to rotate log files and you should copy the
rotated file if needed.
$crontab -l
# backup logs to backup server daily
30 4 * * * /bin/bash /root/logBackup/hostlogBackup.sh