1.
Set a cron job that will be run at 4:30 am on
the 1st and 15th of each month and should execute on every Friday.
30 4 1,15 * 5 command/script
2.
Set a cron job that will run at 1:30 on first
day of every month
30 2 1 * * command/script
3.
Set a cron that will run at 18:45 on every
Friday, but every 3rd month i.e every Fri in Jan, Apr,...
45 18 * */3 5 command/script
4.
Explain the below cron job
23
0-23/2 *
* * command/Script
Above
cron will run at 23 mins after midnight, 2 am, 4am, 6am…. everyday.
5.
Explain the blow cron job
5 4 * * sun command/script
It
will execute at 4:05am on every Sunday.
6.
Explain the blow cron job
20 1
* * *
find /tmp -atime +3 -exec rm -i
{} ';'
Run
at 1:20 am each morning and removes all files in the /tmp dir that have not
been accessed in 3 days.
7.
Explain below command
1 0 * * *
\
cd /tmp; find . ! -name lost+found -type -d -mtime +3 -exec rm -f {} ';'
At
one past midnight, everyday, remove all subdirectories of /tmp which have not
been accessed from last 72 hrs but don’t remove the directory lost+found in
/tmp.
8.
Where would you find the crontab file for user pramod?
/var/spool/cron/pramod
is the crontab file for user pramod
9.
What command is used to modify the crontab?
crontab
-e
10.
What command is used to modify the crontab for
use pramod?
crontab
-e -u pramod
11.
What command is used to list the crontab?
crontab
-l
12.
What command is used to list the crontab of the
user pramod?
crontab
-l -u pramod
13.
What command is used to delete the crontab?
crontab
-r
14.
What command is used to delete the crontab of
the user pramod?
crontab
-r -u pramod
15.
How would you prevent user pramod from creating his
own personal crontab file ?
Add
the entry of user in file /etc/cron.deny
