How to set up a 301 redirect from www to non-www?

Question

1C-Bitrix

Good afternoon!
I read a lot of articles but could not set up the correct redirect from www to without www, tell me how to do it.
Registered in .htaccess:

RewriteCond %{HTTP_HOST} ^www.site_name\.ru$ [NC]
RewriteRule ^(.*)$ http://site_name.ru/$1 [R=301,L]

Everything seems to be working, but if you enter (paste the copied link) www.site_name.ru/catalog/kater-rib/ or another section, a 404 error is issued. When you go through the menu items on the site, everything works.

Answer 1

I made a gluing for the client according to this guide, the subsequent feedback confirmed the correctness of the methodology.

Answer 2

.htaccess is read from top to bottom, moreover, in a circle until the generation of urls stops completely.
Therefore, the location of the directive matters.
All .htaccess to studio