asked on

CRON Spontaneously Shuts Itself Down

System:
The system is an HP 715 running HPUX 10.20

Background:
From time to time and seemingly without reason, CRON will shut itself down. A look at the log file reveals that its last action was to attempt to execute a job in the crontab at an odd time. I've deactivated, then reactivated the crontab which seems to have helped at least for the time being. The problem with this solution is that I've done this before as a quick fix, but the problem resurfaces after a time.

Question:
What could I check to gain a little more visibility into what CRON is doing and when, and how can I prevent CRON from shutting itself down again? What could affect CRON to force it down?

cymru_lad

What do you mean by an 'odd time' ? Also what cron entry was it trying to start ?

As a quick check, check that disk space is available in /var and whether any messages are being logged in /var/adm/syslog/syslog.log. If possible please post the tail entry of the cron log file /var/adm/cron/log.

Mike

ecw

Don't put crap in /var/spool/cron/crontab dir. Only proper crontabs should be here, not backups or the usual dross people leave. I've seen cron die quite often on HP boxes when people have left crap lying around.

pdouglas

ASKER

More Info:

- The system is running CDE (Common Desktop Environment)
- Disk space in /var is at 61%
- Only 1 crontab exists in the /var/spool/cron/crontabs dir.
- The /var/adm/cron/log file does not contain anything unusual.
- The /var adm/syslog/syslog.log *does* contain some odd [or at least I believe they're odd] entries:

DTSESSION: pmauthenticate status=9
DTSESSION: pmauthenticate status=0
inetd[585]: rpc.cmsd/udp: Died on signal 11

jlms

Can't you put the crontab file here?

pdouglas

ASKER

jlms,

I can't post the crontab file here since the system from which it comes is security sensative.

Talmash

type :

crontab -l
to verify if the machine you use for cron job
is not occupied yet .

crontab -r : erase existing cron job from machine :

tip :

you can use those 2 commands while your cron-file .

Talmash

cymru_lad

rpc.cmsd is the CDE Calender Manager Service. I'd check out the latest patches for this and the cron process. Patches are available for download from the HP website.

Mike

tfewster

I don't know if you ever solved this problem, but reading this one and
https://www.experts-exchange.com/questions/20290519/CRON-Appears-to-Start-Itself.html

reminded me of a problem I once saw.

A crontab file automagically reset itself once a day to a "standard" setup, destroying any changes I had made to it. The timestamp on /var/spool/cron/crontabs/username corresponded with the time of a cron job IN the crontab, so it was just a matter of tracing what the cron job did. (in fact, it started a ServiceGuard package, which executed other scripts, one of which was `crontab < /long/and/obscure/path/to/model/crontab` so it took a while to trace it :-)

If your system is doing something similar, it may be that the act of refreshing the crontab is causing cron to hang. Even so, patching cron is recommended.

tfewster

No comment has been added lately, so it's time to clean up this TA.
I will leave a recommendation for this question in the Cleanup topic area as follows:
- PAQ & refund points

Please leave any comments here within the next 7 days

PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER !

tfewster (I don't work here, I'm just an Expert :-)

ASKER CERTIFIED SOLUTION

modulo

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial