Preparing WordPress Multisite behind a Reverse Proxy for SSL (HTTPS)
Enabling SSL (HTTPS) on a WordPress Multisite network can be a bit challenging than it should be, here’s how to do it properly.
The challenge rises its head when you force SSL to be used always, but WordPress was configured using plain HTTP. You might not be able to log in to the dashboard, there can be a redirect loop when you try to access the website, a squirrel might crack a continent — all sorts of things can go bad.
But if you install the plugin “SSL Insecure Content Fixer“, and activate it network wide, we will be able to avoid facing those troubles.
Once network activated, go to your network dashboard (
example.com/wp-admin/network/), and then click
Settings → SSL Insecure Content.
In there, for “Fix insecure content”, select “Simple”. For “HTTPS detection”, select “HTTP_X_FORWARDED_SSL (e.g. reverse proxy)”.