cron not running @reboot command

Question

@reboot commands are not being run from cron. I verified this with

grep cron /var/log/syslog

which showed

Jul 25 16:17:01 picam2 /USR/SBIN/CRON[4487]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Jul 25 17:17:01 picam2 /USR/SBIN/CRON[4497]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Jul 25 18:17:01 picam2 /USR/SBIN/CRON[4507]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Jul 25 19:17:01 picam2 /USR/SBIN/CRON[4623]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Jul 25 19:35:21 picam2 crontab[4714]: (root) BEGIN EDIT (root)
Jul 25 19:36:03 picam2 crontab[4714]: (root) REPLACE (root)
Jul 25 19:36:03 picam2 crontab[4714]: (root) END EDIT (root)
Jul 25 19:58:06 picam2 crontab[4752]: (root) LIST (root)

cron is running

ps aux | grep cron

also setup cron logging by uncommenting the entry in /etc/rsyslog.conf but no /var/log/cron.log is created on the next boot.

From what I can see there should have been a

(CRON) INFO (Running @reboot jobs)

entry followed by

CMD my command

I found the /var/run/crond.reboot file was created 3 days ago even though I had rebooted a number of times. After deleting it and rebooting it has not come back. I thought this was the mechanism cron used to avoid rerunning @reboot jobs?

The crontab was created with sudo and

sudo crontab -u root -l

returns

@reboot echo "hi" > /home/pi/reboot.txt 2>&1
@reboot /home/pi/launcher.sh >>/home/pi/logs/cron.log 2>&1

although it's not directly important, neither the /home/pi/reboot.txt nor the /home/pi/logs/cron.log get created on boot. Both commands work fine when run from a sudo -s shell

New Raspian install (2015年05月05日 image) with apt-get update and apt-get upgrade

Linux picam2 3.18.11+ #781 PREEMPT Tue Apr 21 18:02:18 BST 2015 armv6l GNU/Linux

"man cron" shows this the standard Vixie Cron which does support @reboot

• dhruvvyas90: That's strange. I inserted first line and it works for me. It creates reboot.txt with hi in it.
• rob: do you have the /var/run/crond.reboot file dated from when you booted the Pi?
• dhruvvyas90: Yes. I do have it.
• rob: The only weird thing I can think of that might relate to all this was I ran rpi-update -y when I first setup the Pi and it failed. I had had the exact problem with another Pi a few weeks earlier so I just set the date via ntp and it still failed(even though that had been the fix). and that when ever I delete anything as the pi user it tells me its write protected but lets me delete anyway. Yes, I am clutching at straws now.
• rob: do you had a the INFO (running @reboot jobs) line when running grep cron /var/log/syslog ?

Answer 1

I found the answer and it is so ridiculously simple its scary.

I had been running the same command over and over each time I wanted to reboot, using the shell history.

sudo shutdow -r now;exit

which exited ssh and I thought rebooted the Pi, but no, it was sitting there waiting for me to ssh back in. It should be

sudo shutdown -r now;exit

It works fine now the Pi actually rebooted.