301 redirects against canonical links?

Question

For technical reasons, on the site we may have two or more links related to one product page. For instance:

http://example.com/a-nice-product-no1234.html 

and

 http://example.com/a-nice-foobar-product-no1234.html 

Apparently, the first is the "correct" link. What is the correct approach when opening a second link?

Approach 1)

Redirect 301 to first link

Approach 2)

State 200 and

 <link rel="canonical" href="http://example.com/a-nice-product-no1234.html"> 

in the HTML header? Approach 2) applicable to other search engines than Google? Other offers?

Thanks!

Answer 1

If

 http://example.com/a-nice-foobar-product-no1234.html 

It is in any way invalid or you have the intention to delete it. 301 Moved Permanently is the way to go.

A technical discussion from google from rel="canonical" shows that it should be used to indicate the original content, unlike, for example, the same content ordered differently, using different formatting and so on.

This will also have the advantage of non-bookmarking users and the use of links to these “slightly invalid” pages. Decrease in their use over time.