Hello Guys,
I have been having a lot random e-mails being dropped, so I am trying to go through my server and make sure everything is correct. I ran a DNS report and got a few errors and was wondering what others use for an off location dns server.

"WARNING: All of your nameservers (listed at the parent nameservers) are in the same Class C (technically, /24) address space, which means that they are probably at the same physical location. Your nameservers should be at geographically dispersed locations. You should not have all of your nameservers at the same location. RFC2182 3.1 goes into more detail about secondary nameserver location."

That's not really THAT big a problem, unless you are trying to register domains with some European registrars that require the nameservers to be on different class C's. I don't think I've ever run across a mailserver that will reject mail based on what your DNS server IP's are.

So do most just leave it or do we access to another people use?

The idea behind difference class c networks is to ensure an element of redundency, ie your servers are on difference networks rather than the same network.

I believe that to register a .de domain, your name servers must be on separate class c networks. However, I would not worry about it one bit, it really isn't a major issue. If you are microsoft, you can use akamai to distribute your name servers around the world, but for us mere mortals, just set up your dns and move along.

If you are really worried about it, you could just use The Planet's name servers which are on separate class C networks (actually, separate class As)

Ok thanks. I just want to make sure everything is correct.

Well, that and to make sure they can't all be destroyed in a single natural disaster (ie: fire, earthquake, etc...).

But if your server where your sites are hosted on gets damaged for one reason or another, you still stand to lose everything.

Techically speaking, redundant DNS should also be accompanied by redundant web servers and mail servers.

The likelihood of a DNS failure is rather slim in today's context.

Redundant mail servers are easy, you just add another mail server and its MX record. Redundant web servers are *almost* easy if you are serving static html, just add another server and its A record (I'm hugely simplifying, of course).

Redundant DNS is very important with email - if your smtp client can't resolve the target domain because your DNS is down, it will bin your email there and then. If it can resolve the domain but can't deliver it to any smtp server, it will keep retrying for a period of time. This is one of the reasons why at least 2 and ideally 4 name servers are required when you setup a domain - an unresolvable domain is discarded immediately.

That's a good point that often gets overlooked. If all your nameservers are on one box, even a reboot can cause lost mail.