Imagine I'm proprietor of two domains that are alias, i.e., they point exactly to the same server and folder: exemple.com and exemplo.comHowever, in that server I detect the country of the user, so that, for example:in UK it points to /index_en.html in Spain it points to /index_es.htmlQuestion: Which option is the best internationial SEO practise?allow the crawling of the four combinations, restricting only to exemple.com/index_en.html and exemplo.com/index_es.html and block exemple.com/index_es.html and exemplo.com/index_en.html avoiding thus crawling duplication, ordo not crawl alias and focusing only on one domain, for example example.com and simply make a permanent 301 forwarding from exemplo.com to example.com
Internationial SEO with different alias domains
seo;multiple domains;internationalization
Edit based on Joao's comment*The domains in question are cctld, i.e .es, .it, .pt. Geotargeted subfolders on country specific domains don't work well, if the top level domain is generic (i.e. .com) this solution works. Otherwise, from a pure best for ranking perspective, keeping cctlds that only serve one country is best, but, like every solution, each has it's drawbacks such as additional technical overhead and having to market/optimize each cctld independently rather than consolidating signals to one domain (subfolder approach).Edit endGreat question, I don't fully understand your setup but I think this should describe it and how to deal with it:Where...exemple.com/index_en.html === exemplo.com/index_en.html &&exemple.com/index_es.html === exemplo.com/index_es.htmlSetup:Your 3rd option is best, use 301 redirects to redirect all pages from exemplo.com to exemple.com on a 1:1 basis, i.e. redirect each page to its equivalent. You should determine which domain is the preferred domain by checking which one ranks better/gains more traffic (the preferred domain should also have higher external link count and links from decent websites)The preferred domain in this hypothetical scenario will be exemple.com. When a request originating from a UK IP to exemple.com, you will 302 redirect them to exemple.com/index_en.html. A request originating from Spain with a Spanish IP to exemple.com should 302 to exemple.com/index_es.html.That would be it - don't redirect any other requests on the domain, use hreflang to annotate the spanish and english versions accordingly.I did the Redbull.com setup and a friend of mine did theguardian.com.  We followed Google engineer's advice despite doubting the 302 redirect. The hreflang lead, Christopher Semturs confirmed in a comment on a post I wrote here.I would highly advise you take precaution when consolidating your domains (vigoriously check google search console, run crawls, etc..) and test the international configuration (be ready to roll back immediately) as well.