Open crontab using below command:
crontab -e
Its syntax is like below
* * * * * command/script to be executed/
# Example of job definition:
# .—————- minute (0 – 59)
# | .————- hour (0 – 23)
# | | .———- day of month (1 – 31)
# | | | .——- month (1 – 12) OR jan,feb,mar,apr …
# | | | | .—- day of week (0 – 6) (Sunday=0 or 7) OR sun,mon,tue,wed,thu,fri,sat
# | | | | |
# * * * * * user-name command to be executed
Listing of Cronjobs can be done using below command:
crontab -l
Examples:
1. Take backup every day midnight.
0 0 * * * /my/path/to/script/backup.sh
2. Start mongo server @reboot
@reboot /usr/bin/mongod
3. Mysql database backup every sunday
* * * * 0 /usr/bin/mysqldump -u root -p{root123} userdb2 > /home/nagaraju/myfile_$(date +%Y-%m-%d).sql #every week on Sunday<br />