I have been thinking about how much people are thinking about DNS and I came across the Google Zeitgeist project (http://www.google.com/intl/en/press/zeitgeist/index.html). Basically this is an interface to understand what people are using the Google search engine for. Specifically, I was poking around Insights for Search and queried a few terms related to DNS. The information is fascinating. The most interesting part I noticed is the number of searches and the countries they are coming from. Again, I find this stuff fascinating. We beat the drum each day for DNS and most people never give it a thought, much as it should be, but if you are reading this you probably have a bit more interest. DNS searches have actually decreased over the past few years. Maybe people are more educated? Less concerned? However, DNS attacks are on the rise that is certain.
In our last TechTalk event we had a great number of participants and fielded a lot of questions. There was some good discussion about DNSSEC implementation. Based on what we discussed – you should plan to have your DNSSEC implementations done by the end of 2011, at the latest. Also there were lots of questions about reverse DNS. Reverse DNS is just like DNS but specifically for the IP addresses, for example when you want to know what an IP address points to you would do a reverse DNS query.
The questions were focused on how admins setup a reverse DNS. Reverse DNS is typically maintained by the organization who â€œownsâ€ the IP address(s) or block. In their DNS server they create records for each of their IP address that point to hostnames. Many times those host names will be generic, which is fine. For certain things, especially email, having the hostname come back as generic can create a problem. For example, when you email server attempts to send a message to another server (the receiving server), nine times out of ten, the receiving server will do a reverse DNS lookup on the IP address of the sending server, if the hostname returned is not related to your email zone or if there is no reverse DNS record the receiving server may reject the message. Some email servers can get particularly persnickety about this.
So make sure your reverse DNS ducks are in a row. One of the easiest ways to verify all of your DNS settings is to run a DNSreport at DNSstuff.com. You first need to get a free 21-day trial account to have access to all tools.
Also published on Medium.
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