Place a backup job into your crontabs, for example
* 2 * * * crontab -l > /tmp/crontab.backup
Then you'll have a backup available if you
accidentally delete your crontab. NOTE: All tips provided are USE AT YOUR OWN RISK. Tips are submitted
by various unix admins around the globe. UGU suggest you read and
test each tip in a non-volitile environment before placing into
production.