Cannot install Wordpress Multisite (Network) on a custom port

Question

I'm running a website at http://localhost:8080/sitename. However, when I'm trying to create a network of sites with wordpress, I'm getting the following error under Tools-> Network:

ERROR: You cannot install a network of sites with your server address.
You cannot use port numbers such as :8080.

I tried to create a virtual host and a fake domain but I can't make it work. How can I solve that?

Answer 1

At this moment, Wordpress only seem to support 80 and 443 ports. A temporary possible workaround to use any custom (i.e. http 8080) port:

1. Open wp-admin/includes/network.php and find the section of code where it mentions array( ':80', ':443' ) and add :8080 too in that array.

2. After completing setup of network, you might need in wp-config to adjust to such:
   define( 'DOMAIN_CURRENT_SITE', 'example.com'. (stristr($_SERVER['PHP_SELF'],'wp-login.php') ? '':':8080') );

3. As noted in comments (thanks) after creating first sub-site, it might have port number embedded in domain name, so try to enter Mysql Database (i.e. try hosting's phpMyAdmin, or even installed plugin before starting procedure) and in _blogs & _site& _options tables, to adjust homepage urls of subsites(i.e. separate port number from domain).

4. That's all. Login again to your project.

Answer 2

From my experience, WP is not designed to use custom ports for multi-sites so the blogs (sub-sites) hosts get messed up in the DB.

My solution: After you switch to multi-site or create a new site, you need to go to your db admin page (e.g. phpMyAdmin) and fix the blogs domain in the wp_blogs table. Basically WP failed to add a colon between the host and port; just have to add it-> localhost8080 becomes localhost:8080. So, on the site's settings add the missing colon to the siteurl and home urls.