NU013809@NDSUVM1.BITNET (Greg Wettstein) (01/22/91)
We recently started having problems within on of our XENIX machines which
has me stumped. I have a sneaky suspicion that I have looked at the
problem long enough that I am overlooking something obvious.
The machine under questions is from Gateway 2000 and is a '386DX (33Mhz) with
cache, 8 megabyte RAM, 300 Megabyte hard drive, two serial, parallel, VGA etc.
The XENIX version is 2.3.3 via Update A of vpix.
The machine is very lightly loaded and about three weeks ago I noticed that
cron was executing its assigned tasks twice in very rapid succession. One
of its jobs is to do automated report generating each evening and the boss
started telling me that he was getting two identical reports mailed to him
each evening.
I killed cron, put a LOG=yes in /etc/default/cron to initiate logging and
restarted cron. Sure enough the log entries indicate that everything
controlled by cron is getting run twice typically a couple of seconds
apart. I checked the crontabs file and everything seems correct. I've
killed and restarted cron, stopped and restarted the machine and the
problem persists. A second almost identical machine exhibits nothing
similar.
Like I mentioned previously I may be overlooking something which is too
obvious. If anybody has experienced this or has any suggestions I would
appreciate their comments. Thanks much for any answers which may be
forthcoming. If possible please reply to the address in my signature.
As always,
Dr. G.W. Wettstein
Oncology Research Division Computing Facility
Fargo Clinic / MeritCare
UUCP: uunet!plains!wind!greg
INTERNET: greg%wind.uucp@plains.nodak.edu
Phone: 701-234-2833
`The truest mark of a man's wisdom is his ability to listen to other
men expound their wisdom.'mike@bria.UUCP (Michael Stefanik) (01/24/91)
In an article, Greg Wettstein writes: [...] >The machine is very lightly loaded and about three weeks ago I noticed that >cron was executing its assigned tasks twice in very rapid succession. One >of its jobs is to do automated report generating each evening and the boss >started telling me that he was getting two identical reports mailed to him >each evening. [...] I had a similar problem once. One way to track down when cron is being fired up is to enable process accounting using accton(1), let it run for a day, and then look for cron's using acctcom(1). If you show only one cron being fired up, it could be a problem with your software clock (although this is unlikely). It could be that cron is hosed, but I doubt that too. -- Michael Stefanik, Systems Engineer (JOAT), Briareus Corporation UUCP: ...!uunet!bria!mike -- technoignorami (tek'no-ig'no-ram`i) a group of individuals that are constantly found to be saying things like "Well, it works on my DOS machine ..."
paulz@sco.COM (W. Paul Zola) (02/05/91)
In article <91022.084230NU013809@NDSUVM1.BITNET> NU013809@NDSUVM1.BITNET (Greg Wettstein) writes: [ problems with cron(C) executing jobs twice deleted ] I'm posting this since I thought this might be of general interest. I'd suggest putting the following line in root's crontabs file (/usr/spool/cron/crontabs/root), and then re-starting cron(C). 1 * * * * /bin/true This will force cron(C) to run a job once every hour, and should resolve any scheduling problems you might have. You might also try installing the Support Level Supplement (SLS) xnx155, which contains a new version of cron(C). } Dr. G.W. Wettstein } UUCP: uunet!plains!wind!greg } INTERNET: greg%wind.uucp@plains.nodak.edu - Paul Zola Software Support Engineer paulz@sco.COM Gotta tend the earth if you want a rose. - Emily Saliers DISCLAIMER: I speak for myself, and not for SCO.