Cannot login to Wordpress Admin with SSL terminated load balancer

Question

Running Wordpress 4.7.3 with a HAProxy (version 1.7.2) frontend and Apache 2.4.10 with PHP 5.6 backend.

This is all under Debian 8.7 as well.

X-Forwarded-For and X-Forwarded-Proto are set correctly by HAProxy.

The issue I'm having is when I have SSL terminated on the HAProxy frontend (running http mode) and login to Wordpress Admin I get the error

Sorry, you are not allowed to access this page.

I tried the steps from here but they didn't fix the issue.

At the bottom of my wp-config.php I have

define('FORCE_SSL_ADMIN', true);
// in some setups HTTP_X_FORWARDED_PROTO might contain
// a comma-separated list e.g. http,https
// so check for https existence
if (strpos($_SERVER['HTTP_X_FORWARDED_PROTO'], 'https') !== false)
       $_SERVER['HTTPS']='on';

I tried a clean install of Wordpress (was importing a clients side of an earlier Wordpress for spring cleaning, but that didn't fix the issue either).

Answer 1

I just figured out the issue.

You need to add the HTTPS/SSL settings before require_once(ABSPATH . 'wp-settings.php'); in your wp-config.php

So the relevant part of your wp-config.php should look like this.

define( 'FORCE_SSL_ADMIN', true );

// in some setups HTTP_X_FORWARDED_PROTO might contain
// a comma-separated list e.g. http,https
// so check for https existence
if( false !== strpos( $_SERVER['HTTP_X_FORWARDED_PROTO'], 'https' ) ) {
    $_SERVER['HTTPS'] = 'on';
}

/** Sets up WordPress vars and included files. */
require_once( ABSPATH . 'wp-settings.php' );