Hi,

I have a command that i want to execute and put the results to a file in /var/log called myfile.log. I've put the command into a shell script and when i run the script manually, i get the output on the command line.

When i add a cron job to execute the script and put the same result into the log file, nothing is put in the log file.

Here is my cron job:

*/01 * * * * '/home/nagios/scr/check_oracle_generic.sh > /var/log/app_cron.log'

Here is what /var/log/cron shows:

crond[11014]: (userid) CMD ('/home/anyuser/scr/check_oracle_generic.sh > /var/log/app_cron.log')

so cron runs the command but nothing goes into the log file.

Here are the contents of my script:

#!/bin/sh
/usr/lib64/nagios/plugins/check_oracle_generic -SID=server fqdn
-dbuser=userid -dbpassword=useruser password -w=585 -c=600 -q="select count(*) from c_asset_version where markup_status='PENDING'"

printf "\n" >> /var/log/app_cron.log


This is what should be outputed from this script:

OK=565


Thanks in advance for anyones help

If within the shell script, the putput file is appended to (>>), then why do you have to have the redirect (>) in the cron command?

It looks like the reason - particularly if the shell script works directly. Another thing could be permissions.

end

Did you check the permissions on /var/log? Do they match with those of the script?

I've changes the >> in the script to match what is in the cron and still no success. The permissions on the script and the file its writing to are identical.

Thanks for those tips. If anyone has any other, please let me know.

When you run that script by hand, do you get the desired output on stdout or to the file you specified?

Because what you do is writing doubly: once by "printf" and again by the ">" after your script is run by cron.

Please always repost your script (and crontab) after changes, so we can see exactly what you did.

In a cronjob you don't have access to stdio or stderr. The process may be blocked from running if it prints to stderr. You redirected stdio, but some commands output the information using stderr. Either redirect stderr to stdout or to null.

Thanks for that! So how do i do that? Sorry my scripting isnt that good.

If you put the CRON job in with a 2>&1 at the end, it should burp out the stdio and stderr into the log file.

Thanks tbone and everyone who is trying to help out. I really appreciate it since it is very important for me to get this to work. But tbones suggestion failed also. It just input a blank space into the log file.

Heres why i think its failing. When i run the command or the script manually, the output is return too close to the next prompt and cant interpret any output when run by cron. See example below:

OK: result = 565root@servername:scr#

If there is a way to get the cron to run and return the output on a line above the next prompt? I've edited my script to include sleep. Here is my script below:

#!/bin/sh
/usr/lib64/nagios/plugins/check_oracle_generic -SID=server name -dbuser=dbuser -dbpassword=dbpasswd -w=585 -c=600 -q="select count(*) from c_asset_version where markup_status='PENDING'"
sleep 5
printf "\n" > /var/log/app_cron.log


My cron entry:

*/01 * * * * /home/nagios/scr/check_oracle_generic.sh > /var/log/app_cron.log 2>&1

You still are using ">" instead of ">>" in your cron script. You want to append to a log file and not overwrite it. Change it in both the cron entry and the script. You don't need the sleep command.

I assummed that your script is generalized for this post because the arguments like "-SID=server name" are wrong.

Also consider using the "logger" command to create log entries inside the script, based on the return value of the command.

No i do want the file over written everytime, thats why im using the > and not the >>. As far as the -SID, it needs to be there for the script to work and it runs when i run the command manually command line and when i put it in the script and run it. I just need to know how to get the output to actually dump to a file as it shows command line.

if this is working:

your stdout should already be redirected to the file

and just doing printf "\n" inside the script should already redirected the message to the output file so you don't need to redirect it again

i don't know if your scripts are already working but there are two ways i know on how to do this

(a) first is redirect it in the crontab command:
(b) or redirect it inside the script:

Thanks Konsolebox, i appreciate the input but neither one of these worked. In youre first scenario, the cron ran but nothing wrote to the log file.

But when run command line, the correct output was seen.

In the second scenario, it worked command line but in the log file, it had the following error:

output must be to a tty

or it outputs a single blank space

I then added su - nagios before the exec line and command line it works but still the output desired doesnt rach the log file. UGGG now what?

were you already able to log the output to the logfile by just doing something like this in the command-line?

Yes, running that sends it there. Also when i put that command into a script it works as well. Cron executing the script wont put the result in the log file for some reason.

It only puts in a single blank space or nothing at all or the tty error i listed.