How do I view currently setup or all running cron jobs under Linux operating systems?
The cron service searches its spool area (usually /var/spool/cron/crontabs) for crontab files (which are named after user accounts); crontabs found are loaded into memory. cron also reads /etc/crontab, which is in a slightly different format. Additionally, cron reads the files in /etc/cron.d: it treats the files in /etc/cron.d as in the same way as the /etc/crontab file. The intended purpose of /etc/cron.d/ directory feature is to allow packages that require finer control of their scheduling than the /etc/cron.{daily,weekly,monthly} directories to add a crontab file to /etc/cron.d.View Users Cronjob
Use the following syntax to view username users cronjob:
crontab -u userName -l crontab -u username -l
View Root User Cronjob
Just type the following command:
crontab -l
View /etc/crontab
A cronjob can be also run from /etc/crontab file. To view it, enter:
# less /etc/crontab
View Daily Cronjob
Type the following commands:
cd /etc/cron.daily/ ls -l cat filename
View Hourly Cronjobs
Type the following commands:
cd /etc/cron.hourly/ ls -l cat filename
View Weekly Cronjobs
Type the following commands:
cd /etc/cron.weekly/ ls -l cat filename
View Monthly Cronjobs
Type the following commands:
cd /etc/cron.monthly/ ls -l cat filename
View Software (Package) Specific Cronjobs
Type the following commands
cd /etc/cron.d/ ls -l cat filename