Redirect subdomain homepage to domain specific page in wordpress multisite

Question

I have a wordpress multisite with one site to domain.com and another to materials.domain.com

At the domain site I have a page domain.com/materials

I'd like to redirect the materials.domain.com homepage to the domain.com/materials

I'm using a child theme to my subdomain instalation and trying the following on functions.php

wp_redirect(home_url('https://domain.com/materials'),301);
exit;

Now when I access the materials.domain.com the showed url is https://materials.domain.com/https://domain.com/materials/

What i'm doing wrong? How can I achieve the correct redirection?

Answer 1

Have you tried creating the redirect within the CPanel of wherever your website is being hosted from? I manage all of my redirects there, rather than from within my functions.php. There's a really simple guide on doing that here.

Or is there a specific reason that you would like the redirect to be within the functions.php?

Answer 2

The problem is here:

wp_redirect(home_url('https://domain.com/materials'),301);

home_url adds the home URL to the start of the link. In your case you get something as if you had gone:

$out = "https://materials.domain.com/" . "https://domain.com/materials/";

Instead, try this:

wp_redirect('https://domain.com/materials',301);
exit;

that will send the user to the link without the part you do not want.