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I have two problems with my pi right now.

1) The device won't boot unless I have a HDMI cable plugged in.. I am using it headless, and I'm trying to reduce cable clutter, so needing a HDMI cable to boot the machine is not ideal. It works if I let the pi boot and then plug out the cable.

2) I have problem getting cron to work. I typed crontab -e and added these lines:

*/10 *   * * *   /ks/monitor.sh
@reboot          /ks/monitor.sh

However monitor.sh doesn't seem to run, either at boot or every 10 minutes. I also tried adding it to sudo crontab -e, and edited permissions of monitor.sh to 777. Nothing seems to work.

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1) What options are enabled in /boot/config.txt? 2) Are you very sure that monitor.sh produces output? IE: If you run the script normally, is it fine? – Vincent P Jan 16 '13 at 12:06
Don't forget that cron runs /bin/sh (not bash) with a very limited environment. Your script is probably assuming a more complete PATH definition, so try explicitly adding paths to commands in the script outside /bin, /usr/bin, etc. – scruss Feb 15 '13 at 13:06

This should be 2 questions. I will answer your question about your Raspberry Pi not booting unless the HDMI cable is plugged in.

This seems to be a bug in the firmware. Although it does seem to be fixed in a newer firmware update. Have you tried running rpi-update? Or if you dont have rpi-update, try the following terminal command. Just a note rpi-update will make your RPi more up to date than the following command.

sudo apt-get update && sudo apt-get upgrade
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I am also running my Pi in headless mode w/o HDMI cables plugged in, and it works fine. I am running the 2013-02-09 version of Raspbian Wheezy, plus I have cron-apt running, which automatically upgrades packages. – Arne May 16 '13 at 14:40

First of all; avoid chmod 0777, just use 0711 if you just want to run as root.

Change the crontab entries like this;


*/10 * * * * /bin/sh /ks/monitor.sh
@reboot      /bin/sh /ks/monitor.sh
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