Linux: How to disable IpTables?

To stop the iptables: # /etc/init.d/iptables stop In order to disable the iptables while booting: #chkconfig iptables off to start the iptables: # /etc/init.d/iptables start In order to activate the iptables while booting: #chkconfig iptabes on

Qmail: How to delete old e-mails?

You have checked your mail server’s disk usage and decided to free some space deleting the some of the users emails older than for example 10 days.

Linux: How to monitor the disk usage

In time the disk usage of servers increase and if you do not monitor regularly due to insufficiant disk space your server may not function properly. In order to not to face such trouble it is necessary to follow the disk usage all the time by just creating the shell script file below and adding

Linux: How to auto send email to users exceeding quota

If you want to limit your users disk usage with a quota and notify them automatically whenever they exceet their quota you may write a script like the one below and add it to crontab to run periodically. Add the following line to crontab to run the script every hour