After a lot of debugging, I was able to figure out that Media Temple’s (dv) configuration was responsible for the “Missed schedule” errors I was getting in WordPress. By default, the /etc/hosts file looks like this:
127.0.0.1 yourdomain.com yourdomain localhost localhost.localdomain
To execute cron tasks, WordPress needs to post to the URL http://yourdomain.com/wp-cron.php?doing_wp_cron. This isn’t usually a problem, but with the above hosts file and Plesk’s Apache configuration, that URL will actually result in a 404 error.
I tried removing yourdomain.com and youdomain from the hosts file:
127.0.0.1 localhost localhost.localdomain
127.0.0.1 localhost localhost.localdomain xxx.xxx.xxx.xxx yourdomain.com yourdomain
Now when you restart the VPS, these changes to the hosts file will remain.
I looked at several other possible solutions to fix the “Missed schedule” problem. One solution was setting the “ALTERNATE_WP_CRON” constant in the wp-config.php:
define('ALTERNATE_WP_CRON', true);
This activated some very messy redirecting for the user as they browsed the site though. Not a great solution. Another solution I was considering was just executing wp-cron.php from a cronjob every hour. Something like this:
0 * * * * /home/yourdomain/htdocs/wp-cron.php >/dev/null
Willie Jackson
1. That comment preview feature is sliiiiiick. Nice!
2. This is exactly what I was looking for. I’ll be testing it out this week. Thanks for taking the time to post the solution.
August 5th, 2009 at 6:54am
Ask Questions
Does adding a some cron job help? I got a lot of blogs where i schedule posts. Now i have to keep checking and publishing them. Its made life difficult.
August 7th, 2009 at 2:47am
bradt
Yes, scheduling wp-cron.php to run as a cron job on the server could work as well.
August 7th, 2009 at 2:26pm
Derek
I have two domains on my (dv) account, one for my main site and the other for anything else. Which IP should I be adding there?
Also, I have a crontab running it now, but since I use super cache I get an error email so I would really like to get this working.
August 8th, 2009 at 1:38am
bradt
@Derek If you don’t know the IP addresses for your domains, you should contact Media Temple for support.
August 9th, 2009 at 5:28pm
Derek
I know what my IP’s are, that wasn’t my question. My question was which one do I use?
August 9th, 2009 at 6:33pm
bradt
@Derek If you have two domains with two IP addresses, and your /etc/hosts currently looks like this:
You could try something like this:
If you share 1 ip address between your two domains, you could try:
August 10th, 2009 at 9:11am
Derek
I actually have my main domain on one IP and the other 10 or so sharing the other IP. I’ll try and ask MT and see what they say about it.
August 10th, 2009 at 6:04pm
Emily
Just wanted to thank you for posting this fix, in particular the part about moving the hostname to a second line! Saved me. Cheers.
June 17th, 2010 at 10:34am
(dv) – Shawn Blanc
[...] There were only a few hiccups I encountered. The biggest was that the /etc/hosts file needed editing to work properly with wp_cron.php and the Super Cache plugin (so far as I can tell this is a very [...]
September 27th, 2010 at 8:02am
Hosts file entries for multiple domains on VPS? - Admins Goodies
[...] And those lines must have a few blank lines above the in the hosts file, or they will get overwritten each reboot. See http://bradt.ca/archives/fix-wordpress-missed-schedule-error-on-media-temple-dv-plesk/ [...]
August 17th, 2011 at 12:38am
Wordpress: “Missed Schedule” Problem bei Posts beheben » Admins Werk
[...] ja einem von euch weiter. Die Blogeinträge diesbezüglich (beide in englisch) findet ihr HIER und HIER.crontab.php editierenIst eine absurde Idee, die ich auch in den Weiten des Netzes gefunden habe. [...]
December 17th, 2011 at 6:56am