Linux - SoftwareThis forum is for Software issues.
Having a problem installing a new program? Want to know which application is best for the job? Post your question in this forum.
Welcome to LinuxQuestions.org, a friendly and active Linux Community.
You are currently viewing LQ as a guest. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. Registration is quick, simple and absolutely free. Join our community today!
Note that registered members see fewer ads, and ContentLink is completely disabled once you log in.
If you have any problems with the registration process or your account login, please contact us. If you need to reset your password, click here.
Having a problem logging in? Please visit this page to clear all LQ-related cookies.
Introduction to Linux - A Hands on Guide
This guide was created as an overview of the Linux Operating System, geared toward new users as an exploration tour and getting started guide, with exercises at the end of each chapter.
For more advanced trainees it can be a desktop reference, and a collection of the base knowledge needed to proceed with system and network administration. This book contains many real life examples derived from the author's experience as a Linux system and network administrator, trainer and consultant. They hope these examples will help you to get a better understanding of the Linux system and that you feel encouraged to try out things on your own.
Click Here to receive this Complete Guide absolutely free.
I found a number of threads such as this, but the scenarios are all a little different so I'm starting my own. I'm wondering if this is a permissions thing...Here is the scenario (forgive me if my terminology is off):
Under /var/spool/cron there is an admin crontab with a script that is set to run at 4am every day. The script itself and the content aren't important I don't think because the job itself never runs, but here it is in case it helps:
I followed the troubleshooting tips at http://aplawrence.com/Unixart/crontab_not_running.html: I verified mail can be sent, I checked the logs, made sure crond was running, I added a test script to the admin and root crontabs to write "foobar" to the cron.test document (the second line in the above crontab). The root crontab worked as expected (same script, different directory), and the results of /var/log/cron shows the command running every minute as it should. There is no such result for the same thing for the admin crontab. It shows crontab being reloaded after I make the changes to the file, but that's it. It never appears to run. The article I referenced above mentions something about permissions on the crontab.
In this version of cron, /etc/crontab must not be writable by any user
other than root. No crontab files may be links, or linked to by any
other file. No crontab files may be executable, or be writable by any
user other than their owner.
Could this be my problem? Here are the permissions for the admin crontab:
[root@server ~]# ls -ll /var/spool/cron/admin
-rw------- 1 root root 184 Nov 23 16:36 /var/spool/cron/admin
Do I need to chown and chgrp to admin for this to run?
/var/spool/cron/crontab/<user> should be owned by the user it runs as.
Therefore you need to make /var/spool/cron/crontab/admin owned by user "admin" not user "root".
The admonition about /etc/crontab was not meant to cover all of /var/spool/cron/crontab files. If you had a root file in /var/spool/cron/crontab it should be owned by root but only because root is the user for that file.
No user other than the owner should be able to write to any of the /var/spool/cron/crontab files. Anyone that could write to them could make jobs run as that user.
If the first job fails to run due to a cron issue, root or the job owner should get an email as to why.
Try mailx from the cmd line as both users.
Incidentally, is amalgamaton.sh really spelt like that and not amalgamation.sh ?
Sorry for the radio silence. Unfortunately, this is a client that I only see about once a week so I haven't been back until today.
Yes, amalgamaton.sh is the correct spelling. I checked and made sure that the path indicated in the script is correct as well. I also get no mail for the root user pertaining to this job, nor does the Admin user whose script it is receive any email that the job has failed.
I thought I had changed the ownership after jlightner's post, but after checking permissions again it still shows as owned by user root. I have changed it to admin (again) and will see how that pans out.
Well, I changed the permissions and they stuck and the job is still not running, at all. It's as if crond doesn't even see it. I'm out of ideas other than adding this script to cron.daily and letting it run from there.
Can I add one more thing to this that maybe someone can confirm may or may not be related?
The environment uses Likewise/Samba for authentication. There is a Windows group defined in ADUC, Linux Admins. There is a line in the Likewise config file saying that a user must be a member of this group to log in to the system. The admin account is not a member and therefore cannot directly ssh into the system (this is on purpose). Users can sudo to admin once logged in and run commands however. I also notice that around 4am every day (the same time the cronjob should run for the user admin) /var/log/messages has this entry:
Dec 7 04:00:01 server lsassd: 0xb5552b90:Error: User [admin] not in restricted login list
I'm grabbing at straws and trying to make a connection. I don't see how denying an account the ability to ssh would affect its ability to run a cronjob, especially since users are able to kick off the desired script manually once sudoed to the admin account, but the fact that the error is logged around the same time as the job is supposed to run makes me wonder...
Well, that is indeed the problem! I checked that log and the same message is being reported every minute, right along schedule with the cron job that is trying to run. I have the problem, now I will work on the solution (starting with figuring out what this restricted login list is). Thanks so much for your help!