Most webmasters and search ranking consultants quite often used the Preferrd Domain settings to specify if they want the www.domainname.com or the non-www domainname.com to be indexed by Google. This helped resolve a lot of indexing issues. Unfortunately, Google decided to do away with this important feature.
Google now wants users to specify the preferred prefix for indexing using one of the following:
- Either by using rel=”canonical” tag link in html pages
- Using rel=”canonical” tag in HTTP header
- Specify on a Sitemap
- Or use 301 redirects for retired URLs
This will eventually help Google decide automatically which preferred domain setting to use for indexing. This in one way can regularize webmasters to clean up their SEF Urls and not confuse webmasters but it definitely was one of the commonly used tools when Search Console was called “Google Webmaster”