Question: What does the following error mean:
WARNING: Not all of your nameservers are in different subnets
Answer: If you are receiving this error, it means that the nameservers for your domain are both originating from the same server (or two servers within the same subnet). Generally speaking, this is actually just a warning and not an error. Your server may still function just fine.
To be in full compliance with networking standards, however, you will need to host one nameserver at a different location, or at least on a different subnet. In other words, your domain registrar will require two IP addresses for your nameservers. You can have one on your actual server and have the other hosted on a separate server.
Some web hosting providers will offer remote nameserver hosting as part of their unmanaged dedicated server offerings. If they do not, there are other DNS hosting services that may offer what you need. As a last resort, you can configure your server to use two distinct IP addresses for each nameserver even if they actually both originate from the same place, although this is not ideal.
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