Crontab log

[matteedee]

Hi,

Im new to linux and currently using Ubuntu 10.4LT.

I have been learning the basics of crontab and have managed to run a few dummy taks, however through this process a number of tasks did not work.

This has brought me to the point of thinking,,.. isn't there a crontab log?

I have tried to search for it but nothing appears to be found.

Any help or links to info would be appriciated

Cheers
Matt

[oz]

Hello and welcome to the forums!

Take a look in /var/log for the various log files.

[matteedee]

Hi the following files are in that directory, but there doesnt seem to be anything relating to crontab...

apparmor dmesg kern.log.1 speech-dispatcher
apt dmesg.0 lastlog syslog
auth.log dmesg.1.gz lpr.log syslog.1
auth.log.1 dmesg.2.gz lpr.log.1 syslog.2.gz
boot dmesg.3.gz mail.err syslog.3.gz
boot.log dmesg.4.gz mail.info udev
bootstrap.log dpkg.log mail.log ufw.log
btmp faillog mail.warn unattended-upgrades
ConsoleKit fontconfig.log messages user.log
cups fsck messages.1 user.log.1
daemon.log gdm news wtmp
daemon.log.1 installer pm-powersave.log Xorg.0.log
debug jockey.log pm-suspend.log Xorg.0.log.old
debug.1 jockey.log.1 pycentral.log Xorg.1.log
dist-upgrade kern.log samba Xorg.1.log.old
matt@mattmini:/var/log$

[elija]

I believe that Ubuntu will log cron activity in /var/log/syslog

[matteedee]

That file shows the following:

Oct 31 15:49:15 mattmini anacron[955]: Normal exit (1 job run)
Oct 31 15:56:04 mattmini crontab[2054]: (matt) BEGIN EDIT (matt)
Oct 31 15:57:18 mattmini crontab[2054]: (matt) REPLACE (matt)
Oct 31 15:57:18 mattmini crontab[2054]: (matt) END EDIT (matt)
Oct 31 15:58:01 mattmini cron[958]: (matt) RELOAD (crontabs/matt)
Oct 31 16:06:23 mattmini crontab[2127]: (matt) LIST (matt)


however it doesnt show any tasks that were scheduled in crontab that failed (do to errors in shell scripts)....

how can i find this info in a log?

Thanks

[elija]

I think you have to redirect stderr to a file for the cron job

[lomcevak]

The crontab log will only show when the script ran, it won't show any errors that occured within the script. If you didn't redirect stderr to a file and there were errors then crond should have e-mail them to your linux account. Did you check your mail for your linux account?

# mail

[matteedee]

O.K thanks, im really new to linux, .... could you explain or point me in the way of some info on the following...

stderr and how to configure linux mail?

when i enter 'mail' I get the following output:

matt@mattmini:~$ mail
The program 'mail' can be found in the following packages:
* heirloom-mailx
* mailutils
Try: sudo apt-get install <selected package>
matt@mattmini:~$

[lomcevak]

You are using a linux shell called bash. To get help on bash type:

# man bash

The section you’re currently interested in is Redirection so search for it by typing:

/Redirection

Linux determines where input comes from and output goes to with file descriptors. They are:

0 or stdin which is the standard input
1 or stdout which is the standard output
2 or stderr which is the standard error. That’s where error messages are printed.

By default all three point to your terminal.
It would help if you posted your crontab entry. You probably have your script in crontab as:

/path/to/script > /path/to/log

To get error messages printed in the log as well you need to change it to:

/path/to/script > /path/to/log 2>&1

Now I don’t use Ubuntu but you can try what the error message says to installed those packages. If you are not logged in as root:

# sudo apt-get install heirloom-mailx
# sudo apt-get install mailutils

If you are logged in as root leave off the sudo.

Hope that helps.

[matteedee]

Ok thanks, much appriciated