Our Company has two subdomains like ex1.example.com and ex2.example.com that show exactly one site in one directory in one server. I don't know why they do for two subdomains, but now I work on SEO of their website and want to know, Have this negative impact on SEO? If yes, What Can I do for SEO? I saw the questions that subdomains point to different content, but in this case subdomains point to the same place. Thanks
If two domains have same content and are owned by the same company, then your own pages are competing against yours which in turn will affect your ranking and SEO value is split. There are two different ways to handle it depending on your situation.
If you want both the domains to co-exist:
If you want both the domains to coexist, then you should pick one of your domain as primary domain and do rel="canonical" to your primary domain url. Canonical signals search engines that they are attributed to each other and SEO value gets passed to your primary page.
If you want to shut down one domain and live with the other domain
if you think that you want to avoid the overhead of maintaining two different domains, then you can do 301 permanent redirect to your primary domain from the other domain. After certain point in time, search engines will understand it and start showing up your primary domain. Once the traffic dies to your secondary domain, then get rid of the secondary domain.You should convert your internal links to point to new domain as well.