I have been out of the BP loop for a short while working my hardest trying and succeeding in breaking my home network… but today I have grabbed the latest trunk and discovered that forums will never work on our host provider.

Before anyone thinks that I am getting on some kind of rant… I would like to state that this situation has affected us not only with WordPress MU but with regular WordPress too…

Basically, some webhosting providers that offer shared hosting solutions do not and will find it extremely difficult to enable internal DNS resolutions for your domain…

Example:

mydomain.com = 182.43.21.4.25

But internally, for mydomain.com to look for mydomain.com …DNS will reach the same conclusion for the IP… where in fact, the internal address would more likely be 192.168.1.232.

Even though this sounds confusing, it means that certain features of your WordPress, WordPress MU and BuddyPress will not be available.

To start, if you are running a WPMU site, pingbacks and trackbacks will not work for blogs hosted on the same site… ie ‘mysite.wpmudomain.com’ pings ‘yoursite.wpmudomain.com’, then pingbacks and trackbacks will result in a timeout…

Secondly, wp-cron will not work because the same technique is used to call wp-cron.php.

So basically, I have plopped this forum post on here to explain the limitations that can be encountered purely due to where you host your WordPress/WordPress MU/BuddyPress… and now for the BuddyPress explanation…

BuddyPress Group Forums works by using xmlrpc for communication and thus will never work if your host provider has no internal DNS lookup for your domain.

Without going into even more depth, there are 3 solutions to this situation:

1. Change to a virtual server or someone dedicated to provide what you need
2. Do not worry about Forums and pretend they are not there
3. Plan to write your own BuddyPress implementation

(we are planning the last approach as we are hosted on a very very large datacentre that provides high availability, high bandwidth and low server sharing)

Anyways, I hope I have provided some into an insight on why some users cannot get their forum working. …For info on getting your pingbacks and wp-cron working… visit http://dev.ind-web.com/2008/11/24/trackbacks/ (yups… our blog is a mess… pity ya cant see the local versions yet… should be launched in the new year of 2009 and we will have the plugins available soon too)

[@mgkimsal Member 16 years ago]

I don’t get it. What’s the problem? The forum stuff is still using the full domain name, so any POSTs and such will still go to the right domain, regardless of whether the IP is 192.168.0.1, 127.0.0.1 or 69.93.219.170. I’ve got the forums working on my server just fine, and it doesn’t resolve the internal requests any different than external.

[@burtadsit Participant 16 years ago]

I think he’s talking about *how* domain names get resolved on a shared hosting provider. I ran into problems with domain resolution on my DV. In my case it was just a matter of changing the /etc/hosts file. Since I don’t know what I’m doing in root, it took days to figure out what I needed to change to get xmlrpc working.

I think he’s saying that domain resolution on a shared host can be difficult to control by the user. Me or you as the user on a shared host. Simply because I have a domain hooked up to an ip address doesn’t mean that I have control over *how* that ip address is determined.

1. Lookup ip here in the internal net of the shared provider

2. Lookup ip there in the provider’s name servers

(Return the first ip that I find above)

I think what he’s saying is that the above process will not return the correct ip for the low level stuff that is happening in xmlrpc.

I’m just kinda hazy at the moment as to why the internal ip address is not valid for xmlrpc.

[@rwallen Member 16 years ago]

Just chiming in to say that so far I haven’t experienced any issues with mediatemples shared hosting. xmlrpc is working swell too with the iphone app.

[@burtadsit Participant 16 years ago]

Ya, my prob wasn’t media temple. It was me. I didn’t realize that /etc/hosts was consulted first when looking up an ip address. Thought it all went thru a name server. So it was finding a generic 127.0.0.1 address for my domain. First, and using it of course. Just stupidity on my part.