This error has been messing with me for some time since installing BackupBuddy on my WordPress blog site. You can find some information on this from the BackupBuddy Wiki, but how to fix it is limited. It basically says call your hosting company, or enable WordPress Alternate CRON
HTTP Loopback Connections are not enabled on this server. You may encounter stalled or significantly delayed backups.
I was digging for months and I did enable the Worpdress Alternate CRON in, however I started noticing some odd URL’s showing up that looked like this:
On further investigation, that was showing as at the time the page was hit WordPress was doing a CRON job based on the alternate CRON setup. I wanted to remove this but continued to get the HTTP Loopback error….until! I posted ont eh BackupBuddy forum’s and got a very interesting answer:
"When you mention "what else is this app looking for", BackupBuddy isn't looking for anything, if you want to say that anything is looking for something then it is WordPress that is looking to make an access to the site based on the url of the site - so if you access the site as http://yourdomain.com then WordPress is trying to make an access to that site - simple as that."
Since I own and maintain my own server I have total control over it I read this two or three times and realized the answer was so simple it was silly. All it has to do is with your hosts file. Mine originally looked like this which is pretty standard:
127.0.0.1 localhost localhost.localdomain ::1 localhost localhost.localdomain
Now this is also a single server with a WordPress Multi-Site installation and BackupBuddy uses the parent site as the primary for the backup settings so all I needed to do was add the external DNS to the localhost lines.
127.0.0.1 www.stitchtek.com localhost localhost.localdomain ::1 www.stitchtek.com localhost localhost.localdomain
Now per the reply from the folks at BackupBuddy, the server can ping the WordPress domain name as LOCALHOST. This is not clearly detailed anywhere I have found and yet it was so simple. Problem solved and no more need for the define(‘ALTERNATE_WP_CRON’, true); command and no more crazy URL’s