replaced crontab, now should get crontab back to what it was
I was trying to learn how crontab works. I made a file with an echo command in it and used crontab -u root myfile.
The problem is that when i checked crontab -l i saw that all other jobs were gone and there only was myfile. I used crontab -r in hope that after removing it'll be back to its before jobs. But now when i use crontab -l it says 'no crontab for root'. I tried service crond restart, but no change. How can i get it back to the way it was? Though i had no idea what jobs it had. This is very urgent as i did on an important server.
Thanks for the help in advance.