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Why use MaraDNS?

 

October 6 2012

I had a friend of mine recently ask me why MaraDNS is a DNS server worth using. I gave him this reply.

MaraDNS is a good solution where you need a currently supported cross-platform recursive DNS server with a small binary footprint (under 64k!) and a relatively small memory footprint (about 2-4 megs with the default settings). As an authoritative server, MaraDNS is a good solution if you have relatively few reasonably static domains (IPs don't change very often) and need a DNS server that very quickly fetches records from memory.

MaraDNS makes a lot of sense on low-end low-cost servers (where any file open or fork() is dog-slow) and on systems where the DNS server is best small. MaraDNS also can make sense for embedded systems (OpenWRT, etc.), but keep in mind that its constant malloc()s and free()s of memory is not ideal with some low-end embedded toolkits.

MaraDNS as an authoritative server is a mature product with over a decade of real-world use. Deadwood, the newer recursive server, is younger: It has existed in some form for five years but has only been fully recursive for two; it has had a fair amount of testing in that time frame.

MaraDNS doesn't make sense if you need DNSSEC, full zone transfers, EDNS, or other newer DNS features. MaraDNS doesn't make sense if you need a server that developers are still adding features to: It is a mature and, barring a large inflow of cash or another open-source developer willing to step up to plate, a finished product.

Deadwood turned five yesterday

I just realized that Deadwood turned five yesterday; it now has been over five years since the groundbreaking of the Deadwood project. The reason I started the project is because I wrote MaraDNS' original code too quickly and without knowing all of the corner cases to handle correctly in order to resolve most names on the Internet.

The result of both having to add a bunch of features to handle corner cases in MaraDNS' code and trying to get a working recursive DNS server out there quickly was guacamole code. The code was messy and nigh-to-unmaintainable by the time I was done -- Franky and I spent months chasing down all of the memory leaks before making the 1.0 release over a decade ago.

My plan was always to make a "prototype" recursive DNS server so I could fully understand how DNS works before making the real recursive server. This is why MaraDNS 1.0 used threads: It made implementing recursion that much easier.

Deadwood, MaraDNS 2.0's recursive resolver, is a project I probably should have started 10 instead of five years ago. If everything had been on schedule, it would have taken me about 18 months, not three years, to get the 1.0 release out the door after I started Deadwood. We could have had MaraDNS 2.0 in 2004.

That didn't happen because of open source economics: Since no one was paying me to write this software, I just did not have the motivation to develop it more quickly. Indeed, the only reason I finished up Deadwood's recursion was because I made a promise to myself to have new recursive code out the door before putting MaraDNS on the back burner.

Making MaraDNS and Deadwood has been a lot of fun. It would be wonderful to be in an economic position to be able to actively develop open source again.

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