My Experience in Setting Up DNS Servers on Linux And Free DNS Server ZoneEdit

taragana.com domains (including this site - blog.taragana.com) was using ZoneEdit as DNS Servers. I started using their service while transitioning from VPS hosting to the current dedicated hosting. The service was good and so I didn’t prioritize the effort to move the DNS to my server. After all they had two different servers, what could go wrong?

All was fine and dandy till disaster struck on 19th December (2006 for posterity). The site was down for almost 12 hours when I had an inkling of the problem when I checked AdSense stats (thanks Google!). I didn’t realize it earlier because we use caching DNS server inhouse which masked the problem. After frantic digging around to isolate the cause of the problem I found that neither of the two DNS servers of ZoneEdit were responding. They are ns2.zoneedit.com and ns3.zoneedit.com. I tried changing IP address and back in a lame attempt to fool the server to refresh its cache as I thought that was the problem then. It appeared to work for few hours. Apparently it was just dumb luck. An hour later while I was sleeping the server went down and stayed down ever since (it was finally solved more than a week later).

I had to bite the bullet and start looking at documentation to configure my BIND DNS server. I made it a point to understand each single piece of the puzzle. I wanted to get it right the first time. Within 20 minutes or so I had written named.conf. The writing part was simple, getting to know all the required parts and ensuring that it will be secure and satisfy my needs down the road took some time. I setup one zone per domain and one zone for reverse mapping of all my IP addresses. This is in addition to the default zone for “.” and “0.0.127.in-addr.arpa”.

Configuring the zones wasn’t hard either. I just was careful not to make any silly mistakes. I double checked my CNAME’s and A records. I fetched the data from ZoneEdit screens. Their UI was still functioning.

At this time I noticed ZoneEdit has acknowledged the network issue on their site:

Network Status
Last Update Time: 12/19/06 09:28 am PST

We are currently experiencing issues with NS2.ZONEEDIT.COM, NS3.ZONEEDIT.COM, NS6.ZONEEDIT.COM, and NS17.ZONEEDIT.COM. We are aware of the situation and our engineers are working diligently to get this resolved.

In short I was screwed as both of my servers were down. What is the probability of that happening?

Anyway after double-checking the details I tried to restart named ( /sbin/service named restart ) with some trepidation. I had a closing brace missing typo. After that it started fine.

Now I started toying with nslookup to test the DNS server. Everything looked fine and dandy.

Then I logged in to my domain registrar. I added two subdomains (ns1.taragana.com and ns2.taragana.com) to their Reverse DNS (it helps you to find the DNS servers). Then I updated my DNS server to point to my new DNS servers (ns1.taragana.com and ns2.taragana.com). They are really one server but the custom requires specifying at least two servers.

After that I used dnsreport.com to check my servers and they looked fine. It warned about an SPF record which I added soon thereafter and tested again and it was all peachy. Finally it was time to wait till the information propagated over the net.

Overall I have gained lots of experience in DNS aas a whole and in setting up and updating DNS servers and the whole nine yards. As for free DNS servers like ZoneEdit, you get what you pay for. I strongly recommend anyone with dedicated hosting to setup the DNS servers on their own machines. It is definitely worth the trouble and will save you lots of headaches in future.