Sometimes you'll find that cron stops working and all your News goes stale. Here's a solution.
I use a cron job to update my News feeds. This can be added in the following manner:
sudo crontab -u www-data -e
Now add a line to the crontab:
*/15 * * * * php -f /var/www/owncloud/cron.php > /dev/null 2>&1
Owncloud creates a lock file when the cron.php job is executing which will prevent further instances of cron.php. Unfortunately though you can get into situations where the cron.lock file prevents cron from executing - a dead lock situation:
sudo -u www-data php -f /var/www/owncloud/cron.php
will give:
Another instance of cron.php is still running!
The solution is to simply remove the lock file:
sudo rm /var/www/owncloud/data/cron.lock
Some bright sparks have created an additional cron job to check for the lock file and delete it if is older than 30 minutes:
* * * * * find /var/www/owncloud/data/cron.lock -cmin +30 -delete
Links:
http://doc.owncloud.org/server/7.0/admin_manual/configuration/background_jobs.html#cron