I am building a small unit, based on a Raspberry Pi, to control central heating using a fairly complicated schedule in a building with no wired Internet access.

I am using the Sakis3g script to control a USB GSM dongle (O2, but actually a Huawei dongle).

When I use the sakis3g script standalone, it works fine (everything done as root):

root@raspberrypi:~# ./sakis3g connect APN=m-bb.o2.co.uk
E160 connected to O2 - UK (23410).
root@raspberrypi:~#

But - when I try to run the sakis3g command from within a script executed from cron, it simply doesn't do anything (it just executes for 2-3 seconds and that's it - nothing happens).

Output from /var/log/syslog:

Jan 18 11:26:01 raspberrypi CRON[5302]: (root) CMD (/root/networkon.sh)
Jan 18 11:26:04 raspberrypi CRON[5298]: (CRON) info (No MTA installed, discarding output)

The script which is run from cron:

root@raspberrypi:~# cat /root/networkon.sh
#! /bin/sh

./sakis3g connect APN=m-bb.o2.co.uk
root@raspberrypi:~#

The root crontab entry:

# For example, you can run a backup of all your user accounts
# at 5 a.m every week with:
# 0 5 * * 1 tar -zcf /var/backups/home.tgz /home/
21 * * * * /root/networkon.sh

Anyone any ideas please??

Replace this part of your script
with the full path to sakis3g

1 members found this post helpful.

^ it might help, but it might not.
i had some experience with sakis3g some time ago.
i came to the conclusion that it's a horrible mish-mash of scripts cludged together with hotsnot. no idea how it will behave when called form cron (i did indeed have a similar problem with it).
it's good because ~10years ago it was able to recognize simply everything, and connect.
but nowadays, i don't know if it's even maintained anymore.
if you can, don't use it.

Also cron is to be treated like a user. It has to have access to all that you have when your run this script.

Thanks, TenTenths, in fact I did have the full path to sakis3g (the line in the post was a cut-and-paste error).

You are right, Ondoho - it is a terrible mish-mash - but in fairness it DID download and immediately work with my modem/carrier combination (O2) and I had it running standalone within 5 minutes, it just wouldn't work from cron.

BUT - I have now got to the bottom of it - after much digging around!

For some bizarre reason I don't understand (because the whole thing is running as root anyway) one has to add the "--sudo" line to the command before it will work from cron, i.e.

/root/sakis3g --sudo connect APN=m-bb.o2.co.uk

and now all is working!

Thanks for your input

Cron is not root.