I have a VPS server that I host several sites on. One of the domain names I use for a site hosted on the VPS is registered through a different company, Host Gator. The site was working fine until this morning when it randomly went down. After hours of talking to Host Gator support, they decided that the problem was I did not have an A record for "NS1" and "NS2" pointing to my name server's ip addresses and they claimed the absence of those A records are why the site went down.
I have never heard of needing an A record for "NS1" and "NS2" before. I am confused as to why the site would work just fine without the A records and then suddenly go down when no DNS changes were previously made. Could someone explain this to me?