Cron – Where does Cron checks the time zone on Debian

crontimezone

I have seen number of topics that are related to my question, but non of them answers it.

Where does Cron look-up the time zone ?

root@awesome:~# date
Fri Feb 17 14:02:02 EET 2012

root@awesome:~# hwclock -r
Fri 17 Feb 2012 14:03:39 EET  -0.815689 seconds

But the Cron still works on GMT zone. (I have to make every cron job +2h to make it run properly on time)

Is there mistakes in time-zone configuration ? Or there are more time-zone configuration on Debian Linux, and I am configurationg in on the wrong one ? (I have configured my time zone via tzselect

Best Answer

You have to restart the cron daemon for the time zone change to take effect.

Ref: http://wiki.debian.org/TimeZoneChanges

Direct quote from the above link...

Restarting Daemons and Long-Running Programs

After the zoneinfo files are updated, you may need to restart daemons and other long-running programs to get them to use the new zone information. Examples of such programs include apache, bind, cron, fetchmail -d, inetd, mailman, sendmail, and sysklogd. A common symptom of this problem is seeing incorrect timestamps mixed in with the correct timestamps in your log files (e.g. /var/log/syslog). Even interactive programs like "mutt" may continue to use the old timezone information until they are restarted.

Related Solutions

Linux – A cron replacement that handles multiple time zones

I think you're trying to have it both ways and the reality is that you just can't. If you want a job to run at 8 AM local time, for example, regardless of whether daylight saving is active then you either run your system (and cron) in local time and don't do seasonal edits or you run it in UTC (not GMT) and do seasonal edits. If you want your jobs to run at the same UTC, regardless, then you run cron according to UTC and there's nothing more to do.

If what you want is for a user to be able to schedule a cron job according to his local time zone and not have him have to think about conversions for his convenience then you write a conversion script that accepts a cron spec and a time zone then does the conversion to UTC behind the scenes and edits the crontab for him. It could even be a two-way conversion to handle changes to existing entries.

It will be helpful if you tell us what you're actually trying to accomplish.

Bash – Command does not execute in crontab while command itself works just fine

On a default UNIX-like system, cron has a minimal environment defined. Usually HOME, SHELL, LOGNAME are defined and PATH is set to /bin.

You have two solutions:

enter the full path of your script. ie: /home/me/bin/ec2-automate-backup.sh
alter the PATH environment variable.

If you want to receive email from the cron daemon define the MAILTO variable.

MAILTO=me@example.org
PATH=/bin:/home/me/bin
*/5 * * * * ec2-automate-backup.sh -v "vol-fb2fbcdf" -k 3
# OR
*/5 * * * * /path/to/script/ec2-automate-backup.sh -v "vol-fb2fbcdf" -k 3

Best Answer

Restarting Daemons and Long-Running Programs

Related Solutions

Linux – A cron replacement that handles multiple time zones

Bash – Command does not execute in crontab while command itself works just fine

Related Topic