Make non-existent sub-domains redirect to main domain

Have you met my friend define( 'NOBLOGREDIRECT', '' ); ?

define( 'NOBLOGREDIRECT', 'http://maindomain.com' );

Enjoy 😀

but I want other sub-domains (say if someone mistypes) to just redirect to our main domain.

That’s what you said you wanted. Now you’re saying that’s NOT what you want?

You can wrap that define around some PHP code.

if domain is domain1, redirect to maindomain1.com
if domain is domain2, redirect to maindomain2.com

So then it’ll call the noblogredirect dependant on what domain.

OR you can have PHP check for the main domain and make a variable and use that in the define.

You have to give us a clear example/representation of your setup and needs if you want to have any hope for a complete answer, just FYI. I mean, I can only help what you tell me 🙂 The best solutions aren’t always applicable all around because we want to keep things as simple as possible to reduce overhead.

So!

In some installs we do want any non-recognized sub-domains to redirect to the main domain but on others (like multisites that use sub-domains) we want unrecognized sub-domains to redirect to that main site, not the base site it was installed under if it’s different.

Then my second suggestion IS what you want.

$domain = $_SERVER['SERVER_NAME'];
$domain = str_replace('www.', '', $domain);
if ($domain == 'seconddomain.com') {
   define( 'NOBLOGREDIRECT', 'http://seconddomain.com' );
} elseif ($domain == 'thirddomain.com') {
   define( 'NOBLOGREDIRECT', 'http://thirddomain.com' );
} else {
   define( 'NOBLOGREDIRECT', 'http://maindomain.com' );
}

So what this does is say ‘If I’m second domain, redirect there, and third domain ditto, but all else default to maindomain.’ That would cover multinetworks too 🙂