crontab fails to write logs

Navid777

11/30/22, 9:21 AM

I'm using crontab to run a python script every minute. This is my how my crontab file looks like:

*/1 * * * *  source /root/.bashrc && source /home/env/bin/activate && python /home/manage.py shell < /home/script.py  >> /var/log/navjob.log 2>&1

When try to check cron output in syslog with this command #grep CRON /var/log/syslog the output is like this:

...CRON[764888]: (root) CMD (source /root/.bashrc && source /home/env/bin/activate && python /home/manage.py shell < /home/script.py  >> /var/log/navjob.log 2>&1)
...CRON[764887]: (CRON) info (No MTA installed, discarding output)

But the log file (/var/log/navjob.log) is empty and the code is not run!

1 + 0

cron

django

Score:2

Ubuntu

steeldriver

11/30/22, 1:15 PM

When you chain commands and add redirection like

cmd1 && cmd2 && cmd3 >> somefile 2>&1

(or cmd1 ; cmd2 ; cmd3 >> somefile 2>&1 etc.) the redirections only apply to the last command in the chain. To redirect all of them, you need to group the commands like

{ cmd1 && cmd2 && cmd3 ; } >> somefile 2>&1

or (with a subshell)

( cmd1 && cmd2 && cmd3 ) >> somefile 2>&1

In this case, your cron job is likely failing at the very first source command, since source is a bashism and cron's default shell is /bin/sh - either add SHELL=/bin/bash before the crontab entry, or change source to the POSIX .

0 + 0

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: crontab fails to write logs

TH: crontab ไม่สามารถเขียนบันทึกได้

RO: crontab nu reușește să scrie jurnalele

RU: crontab не пишет журналы

VI: crontab không ghi nhật ký

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