CRON has several options but we’ll discuss it generally by assuming you are root user. The default root script of cron can be found in /var/spool/cron/root where “root” is the user and the file contains command or scripts to execute at a given time.
CRON has the follow syntax:
[root@server01 ~]# vi /var/spool/cron/root
CRON has the follow syntax:
[root@server01 ~]# vi /var/spool/cron/root
30 15 * * * sh /root/scripts/clear_squid.sh
This means every on 3:30pm, it will run clear_squid.sh. if you want to add more scripts, simply add it under the last schedule.
[root@server01 ~]# mkdir scripts
[root@server01 ~]# cd scripts
[root@scripts ]# vi clear_squid.sh
Bash scripting:
#!/bin/bash
rm /var/log/squid/* -Rf
rm /var/spool/squid/* -RF
/sbin/service squid restart
exit 0
The first line tells the script is bash and it tells where to find the interpreter / second line tells the command to delete all squid logs / third line tells the command to delete all squid cache / fourth line tells the command to restart squid / fifth line tells the command to exit properly with status 0 After making the script you have to change the file properties so it will be executable
[root@scripts ]# chmod 744 clear_squid.sh
You can either run the file manual or have it scheduled will do the same.
This means every on 3:30pm, it will run clear_squid.sh. if you want to add more scripts, simply add it under the last schedule.
[root@server01 ~]# mkdir scripts
[root@server01 ~]# cd scripts
[root@scripts ]# vi clear_squid.sh
Bash scripting:
#!/bin/bash
rm /var/log/squid/* -Rf
rm /var/spool/squid/* -RF
/sbin/service squid restart
exit 0
The first line tells the script is bash and it tells where to find the interpreter / second line tells the command to delete all squid logs / third line tells the command to delete all squid cache / fourth line tells the command to restart squid / fifth line tells the command to exit properly with status 0 After making the script you have to change the file properties so it will be executable
[root@scripts ]# chmod 744 clear_squid.sh
You can either run the file manual or have it scheduled will do the same.
U needs to restart Crond:
[root@scripts ]# service crond restart
You can list active cron task with the following command:
[root@scripts ]# crontab –u root –l
[root@scripts ]# service crond restart
You can list active cron task with the following command:
[root@scripts ]# crontab –u root –l
Credits: nsharif.blogspot.com