topic Re: Cron Question in Operating System - HP-UX

Cron Question

Hunki — Thu, 13 Jul 2006 09:56:20 GMT

While updating crontab with crontab -e and then saving them with :wq ... the entries vanish after I disconnect for the shell ... this is happening for a regular non root user.
Have you guys faced this before...

Thanks

Re: Cron Question

Steven E. Protter — Thu, 13 Jul 2006 10:01:21 GMT

Shalom,

Yes,

I've seen this happen when the users didn't have rights to his/her own file in /var/spool/cron

I've seen in when some other process overwrites all the cron files, perhaps a root cron job.

SEP

Re: Cron Question

Jaime Bolanos Rojas. — Thu, 13 Jul 2006 10:01:35 GMT

Hunki,

Please check to see if you have a /var/adm/cron/cron.allow and cron.deny,
check the permissions to see if the user has the rights to use cron.

Regards,

jaime.

Re: Cron Question

A. Clay Stephenson — Thu, 13 Jul 2006 10:03:56 GMT

You shouldn't be using crontab -e; as you have discovered it's a potentially dangerous shortcut. You should do it like this:

crontab -l > myfile
vi myfile
crontab < myfile

You then always have a backup file. However, the crontab command is always porentially dangerous because if you do this:
crontab
then crontab is waiting for stdin and will overwrite your existing entry with a null entry.

I suspect what is really happening is that you have users that are simply typing "crontab" without either a -e or -l argument.

In any event, I still suggest that you not use -e.

Re: Cron Question

MarkSyder — Thu, 13 Jul 2006 10:27:39 GMT

Clay is giving you good advice, as e (edit) and r (remove) are next to each other on the keyboard.

My solution to this problem is to run a cron job that backs up the crontab file every Sunday. That way I can use crontab -e without worrying.

Mark Syder (like the drink but spelt different)

Re: Cron Question

OldSchool — Thu, 13 Jul 2006 10:34:10 GMT

You shouldn't be using crontab -e; as you have discovered it's a potentially dangerous shortcut. You should do it like this:

crontab -l > myfile
vi myfile
crontab < myfile

That's the *only* way I edit them!