Crontab Permission Denied

Question

I'm having problem with crontab when I'm running a script.

My sudo crontab -e looks like this:

05 00 * * * /opt/mcserver/backup.sh
10 00 * * * /opt/mcserver/suspend.sh
05 08 * * * /sbin/shutdown -r +1
11 11 * * * /opt/mcserver/start.sh  <--- This isn't working

And the start.sh looks like this:

#!/bin/sh
screen java -d64 -Xincgc -Xmx2048M -jar craftbukkit.jar nogui

and have these permissions (ls -l output)

-rwxr-xr-x 1 eve eve  72 Nov 24 14:17 start.sh

I can run the command from the terminal, either using sudo or not

./start.sh

But it wont start with crontab. If i do

grep -iR "start.sh" /var/log

I get the following output

/var/log/syslog:Nov 27 11:11:01 eve-desk CRON[5204]: (root) CMD (eve /opt/mcserver/start.sh)
grep: /var/log/btmp: Permission denied
grep: /var/log/lightdm/x-0-greeter.log: Permission denied
grep: /var/log/lightdm/lightdm.log: Permission denied
grep: /var/log/lightdm/x-0.log: Permission denied

So my question is, why isn't it working? And since my script run without using sudo, I don't necessarily need to put it in sudo crontab?

( and I'm using Ubuntu 12.10 )

Thanks in advance, Philip

---

Answer to twalberg's response

1. Changed owner on craftbukkit to root, to see if that fixed the problem.

-rw-r--r-- 1 root root 12084211 Nov 21 02:14 craftbukkit.jar

and also added an explicit cd in my start.sh script as such:

#!/bin/sh
cd /opt/mcserver/
screen java -d64 -Xincgc -Xmx2048M -jar craftbukkit.jar nogui

2. I'm not quite sure what you mean here. Should I use the following path in my start.sh file when i start java? (output from which java)

/usr/bin/java

3. When my server closes, screen is terminated. Is it a good idea to start screen in "detached mode" anyway?

Still got the same "Permission denied" error.

---

Problem solved! By using the proper flag on screen, as below, it is now working as it should!

screen -d -m java -d64 -Xincgc -Xmx2048M -jar craftbukkit.jar nogui

Thanks a lot to those who answered, and especially twalberg!

Answer 1

start.sh is owned by "eve:eve" and your crontab is running as root.

You can solve this by running following command

chown root:root /opt/craftbukkit/start.sh 

Your crontab will be running as root though.

Tip: When running bash in crontab always use absolute paths (it will make debugging a lot easier).