Are There Dangers in Sharing One Nameserver For Multiple Websites?
For large companies and organizations with multiple websites, which often house similar content, it’s common to have domains spread across multiple hosts, and therefore, multiple nameservers. The opportunity may arise, however, to consolidate all sites under one hosted DNS and thus decouple the hosting from the nameservers. Businesses typically consolidate nameservers in order to ease DNS control, rather than for SEO purposes. But will using the same nameservers for multiple websites carry with it any negative SEO implications?
One major benefit of decoupling the hosting from the nameservers is that you introduce an additional layer of DNS verification. Once decoupled, DNS and web hosting for multiple websites are not going to all be hosted by the same company, so the IPs – and therefore, the physical location of DNS vs. the physical location of hosting – will most likely be different.
On the other hand, Google can still do NS (short for nameserver) lookups to see that the DNS settings between the sites share similar nameservers. The train of thought that could lead you down the wrong path is something like this: “When Google does NS lookups on my site, the number of sites on the nameserver will most likely be greater than there would be at the hosting company and that should make it harder for them to see that I have similar websites”.
Use caution with this train of thought. The setup is still similar. In order to manage your DNS, a DNS provider still has nameservers that are associated with IP addresses. While they may manage many site’s associated DNS settings, they will still only place a certain number of sites on one nameserver before spinning up another nameserver (the point being that there aren’t going to be a huge amount of sites associated with one IP address).
What About Google?
Both Google and any web administrator can check against the IP address(es) of the nameserver(s) to see what other domains are associated with each IP address. If all company sites are on the same nameserver, Google or any web administrator will be able to make a connection due to factors like similar topics, similar products, similar content, similar site layouts, similar physical locations, similar tracking codes, etc.
Ideally, all signals (similar topics, similar products, similar content, similar site layouts, similar physical locations, similar tracking codes etc.) would be addressed before proceeding (by consolidating or removing similar content), because addressing just one signal will not make a huge impact. But if all the other signals must remain unchanged and in place, then the ideal setup would be to have your DNS vendor control the DNS for each site, but on separate nameservers for each site. Separate nameservers should, in turn, give you separate IP addresses and therefore add a layer of DNS verification to your domains.
So the answer to the question – “Will using the same nameservers for multiple websites carry with it any negative SEO implications?” – is no, but there is a bigger question here. Does your group of company sites have similar signals (similar topics, similar products, similar content, similar site layouts, similar physical locations, similar tracking codes, etc.)? If they do have similar signals, consider consolidating the similar sites into one as the first choice solution to fix this problem. Choose the site that gets the most organic traffic and let the other sites’ content support this site. There are steps a company can take to pass traffic from any of these other company sites to the preferred site with minimal dip in overall traffic. Contact us today for assistance with your site migration or consolidation project.
For reference, here are some of the tools we use when looking into hosting and DNS settings.
http://mxtoolbox.com/DNSLookup.aspx – DNS lookup – tells where the site is hosted by giving the IP address (once DNS lookup is complete, you can follow it up with an NS lookup)
http://www.majesticseo.com/reports/neighbourhood-checker – neighborhood checker (see what other domains are associated with your IP address)
http://netcomber.com/ – tool to find similar websites (links, technology, contact details, tracking accounts and hosting details), created by former Google search quality team member.