stop cron from sending mail

jmooers · 05-25-2005, 01:27 PM

Hi all,

I am new to cron, but have (with the help of the mailman list) figured out a way to create a cron event. The problem is that I am now getting an email everytime the script runs. I have no interest in receiving this message every 15 minutes of the day.

Running OS 10.3.9 Server on a colo Xserve. Any help would be greatly appreciated.

csdk0713 · 05-25-2005, 04:51 PM

Add this to the end of your cron line:

Code:

>/dev/null 2>&1

So you'd have:

Code:

15 * * * *  runme.sh >/dev/null 2>&1

nkuvu · 05-25-2005, 06:21 PM

That will redirect the output of whatever command to /dev/null, but cron will still email status messages. What you need to do is set MAILTO to null. The syntax (in your crontab file) is:

MAILTO=""

Note that this was covered in another recent thread.

update: miscopied the thread address (left off an 8). thanks for the catch, cpragman

cpragman · 05-26-2005, 05:28 AM

Actually, it's this thread.

Put the parameter on a line by itself in the crontab file (i.e., at the top of the file).

Code:

MAILTO=""

For example, here's a copy of my user's contab file now...

Code:

#
#
MAILTO=""
#

 30     *       *       *       *       /Users/Shared/Staff/Applications/sharenice.csh
 @reboot cd /Users/cpragman/Applications/FAH5; ./fah5 -local -advmethods -forceasm -verbosity 9 &
#SqzS   VERSION = 1.0.0
#SYMANTEC SCHEDULER CRON ENTRIES.  THESE ENTRIES ARE AUTOMATICALLY GENERATED
#PLEASE DO NOT EDIT.
# Enc=1 Name="FileSaver Daily Update"  EvType1=3 EvType2=0 Sched=3
 0 12 * * * "/Library/Application Support/Norton Solutions Support/Scheduler/schedLauncher"  0  "/Library/Application Support/Norton Solutions Support/Norton Utilities/Norton Volume Assist"  "    "  "oapp"  "aevt"  "exAG"  "-d0"
# Enc=1 Name="Daily Defragmentation"  EvType1=4 EvType2=0 Sched=3
 0 0 * * * "/Library/Application Support/Norton Solutions Support/Scheduler/schedLauncher"  0  "/Library/Application Support/Norton Solutions Support/Norton Utilities/Norton Defragger"  "    "  "oapp"  "aevt"  "exAG"  "-d0"
# Enc=1 Name="Update Virus Protection"  EvType1=1 EvType2=0 Sched=1
 0 18 1 * * "/Library/Application Support/Norton Solutions Support/Scheduler/schedLauncher" -u  0  "/Applications/Norton Solutions/LiveUpdate.app/Contents/MacOS/LiveUpdate"  "    "  "oapp"  "aevt"  "exAG" "-update LUdf"
#SqzS END SYMANTEC CRON ENTRIES

It works. Just note that you won't get any mail from cron for the user in question.

jmooers · 05-26-2005, 09:43 AM

Quote:

Originally Posted by nkuvu


	That will redirect the output of whatever command to /dev/null, but cron will still email status messages. What you need to do is set MAILTO to null. The syntax (in your crontab file) is: MAILTO="" Note that this was covered in another recent thread. update: miscopied the thread address (left off an 8). thanks for the catch, cpragman

Thanks for the replies. I did the above, will see if it works. Sorry about reposting after the issue had already been addressed in a previous thread. I did search the archives, but did not see it.

csdk0713 · 05-27-2005, 12:54 PM

The MAILTO thing is great if you never want to receive email from cron, but when debugging an automated process, sometimes you want to receive mail from one or more (but maybe not all) cron jobs. That's why I usually do it line by line as listed above. It's all about having options.

jmooers · 05-27-2005, 03:01 PM

Well I tried it but it did not work.

I added

MAILTO=""

to my /etc/crontab file. It is for user mailman, who as far as I can tell does not have its own crontab file. Any other suggestions?

nkuvu · 05-27-2005, 03:38 PM

After you add the MAILTO to the cron file, you have to tell crontab to update it:
crontab filename

It doesn't happen automagically. Did you do this?

jmooers · 05-31-2005, 01:36 PM

Ok, so I have restarted the script, as described above. I am still getting emails. Here is a copy of my /etc/crontab file.

Quote:


	# /etc/crontab SHELL=/bin/sh PATH=/etc:/bin:/sbin:/usr/bin:/usr/sbin HOME=/var/log MAILTO="" # #minute hour mday month wday who command # #/5 * * * root /usr/libexec/atrun # # Run daily/weekly/monthly jobs. 15 3 * * * root periodic daily 30 4 * * 6 root periodic weekly 30 5 1 * * root periodic monthly

Now that I look at the above code, I don't see the script, thought it is clearly running. The user is mailman. Is there another file that I should be looking for? I am running this through webmin. I do know how to use the terminal and pico into a file as well.

Thanks for your patience.

cpragman · 05-31-2005, 03:09 PM

If you modified /etc/crontab, then you changed ROOT's behavior, so you shouldn't get any more e-mails from the various root maintenance tasks that run.

If you have users with cron scripts, they are edited a different way. Check out man crontab. You can't really edit a user's cron file directly. The closest you can come is "crontab -e username", which will open a vi editor session of the username in question's crontab file. (You might need "sudo crontab -e username" for a user other than yourself).

If your system has an imaginary user names mailman that is generating the e-mails, then you need to "sudo crontab -e mailman", and add the MAILTO="" line to that users crontab file.

ajp · 05-31-2005, 03:59 PM

i use this quick bash script to track down weird cron entries.

Code:

#!/bin/sh
for name in `nireport . /users name`; do
	echo -n "$name: "
	sudo crontab -u $name -l
done

05-25-2005, 01:27 PM	#1
jmooers Prospect Join Date: May 2005 Posts: 4	stop cron from sending mail Hi all, I am new to cron, but have (with the help of the mailman list) figured out a way to create a cron event. The problem is that I am now getting an email everytime the script runs. I have no interest in receiving this message every 15 minutes of the day. Running OS 10.3.9 Server on a colo Xserve. Any help would be greatly appreciated.

05-25-2005, 04:51 PM	#2
csdk0713 Prospect Join Date: Dec 2004 Posts: 39	Add this to the end of your cron line: Code: >/dev/null 2>&1 So you'd have: Code: 15 * * * * runme.sh >/dev/null 2>&1

05-25-2005, 06:21 PM	#3
nkuvu MVP Join Date: Jun 2002 Location: Tucson, Arizona Posts: 1,236	That will redirect the output of whatever command to /dev/null, but cron will still email status messages. What you need to do is set MAILTO to null. The syntax (in your crontab file) is: MAILTO="" Note that this was covered in another recent thread. update: miscopied the thread address (left off an 8). thanks for the catch, cpragman Last edited by nkuvu; 05-26-2005 at 09:24 AM.

05-31-2005, 03:59 PM	#11
ajp Triple-A Player Join Date: Oct 2003 Location: Philadelphia, PA, USA Posts: 80	i use this quick bash script to track down weird cron entries. Code: #!/bin/sh for name in `nireport . /users name`; do echo -n "$name: " sudo crontab -u $name -l done

05-27-2005, 12:54 PM	#6
csdk0713 Prospect Join Date: Dec 2004 Posts: 39	The MAILTO thing is great if you never want to receive email from cron, but when debugging an automated process, sometimes you want to receive mail from one or more (but maybe not all) cron jobs. That's why I usually do it line by line as listed above. It's all about having options.

05-27-2005, 03:01 PM	#7
jmooers Prospect Join Date: May 2005 Posts: 4	Well I tried it but it did not work. I added MAILTO="" to my /etc/crontab file. It is for user mailman, who as far as I can tell does not have its own crontab file. Any other suggestions?

05-27-2005, 03:38 PM	#8
nkuvu MVP Join Date: Jun 2002 Location: Tucson, Arizona Posts: 1,236	After you add the MAILTO to the cron file, you have to tell crontab to update it: crontab filename It doesn't happen automagically. Did you do this?

05-31-2005, 03:09 PM	#10
cpragman All Star Join Date: Jan 2004 Location: Limerick, PA Posts: 858	If you modified /etc/crontab, then you changed ROOT's behavior, so you shouldn't get any more e-mails from the various root maintenance tasks that run. If you have users with cron scripts, they are edited a different way. Check out man crontab. You can't really edit a user's cron file directly. The closest you can come is "crontab -e username", which will open a vi editor session of the username in question's crontab file. (You might need "sudo crontab -e username" for a user other than yourself). If your system has an imaginary user names mailman that is generating the e-mails, then you need to "sudo crontab -e mailman", and add the MAILTO="" line to that users crontab file.