Configuration of crontab in Linux

# Configuration of crontab
--------------------------
# Crontab is actually useful for sceduled tasks.

# Crontab file contains five fields as,
* * * * *
# First * represents : Minute(0-59)
# Second * represents : Hour(0-23)
# Third * represents : Day of Month(0-31)
# Fourth * represents : Month(0-11)
# fifth * represents : Day of week(0-6) 0=Sunday

# Configuration Steps:
----------------------
crontab -u user1 -e
0 4 * * 1,3,5 /sbin/echo "Hello World"
0 0 31 10 * /sbin/ifconfig eth0
* * * * * /sbin/echo "hello"
:wq

# Turn on the services and daemons
chkocnfig crond on
service crond restart

# To check out the crontab
mail