Redirect via dns?

Question

Domain Name System

There is a website, let's call it simple.php. It has a shop.simple.ru subdomain, it should have a redirect to the main resource because of the entry:
shop.simple.ru.
CNAME
simple.ru (value)
But the redirect does not occur, simple.ru is opened to shop.simple.ru. What is the problem, in the guides they write that CNAME should be enough?

Answer 1

That's right, CNAME is an alias, i.e. second\alternative resource name. This is how it should happen.
The redirect must be done at the level of the web server, or whatever you have.

Answer 2

A CNAME (Canonical Name) record allows you to assign mnemonic names to a host. Mnemonic names, or aliases, are widely used to associate a function with a host, or simply to shorten a name.