Friday, January 25, 2013

Install djbdns on Raspberry Pi

Install djbdns on Raspberry Pi

djbdns is a small, fast, and secure DNS server. Perfect for low resource systems. I also find it easier to configure than BIND (once you understand how).
I start with a raspbian image from

Install some packages that D. J. Bernstein says that we need.
apt-get install ucspi-tcp apt-get install daemontools

Don't install tinydns. It includes a pop3 server.
Install djbdns following

Create some users and groups that we will need for executing the dnscache and multilog.
useradd svclog useradd dnscache

Create the /etc/dnscache folder structure
dnscache-conf dnscache svclog /etc/dnscache

Setup /service directory, svscan looks at this directory to see which services to run.
mkdir /service ln -s /etc/dnscache /service/dnscache

Add the following to /etc/rc.local so that the supervised services start on boot.
/usr/bin/svscanboot &

svscanboot also needs the following link to function correctly.
ln -s /service/ /etc/service

Optional Things

Update /etc/dnscache/env/IP to contain the ip address to listen on. Also create a file entries in /etc/dnscache/root/ip to specify the networks that the dns server should reply to.

Edit /etc/dnscache/log/run adding s52428800 before ./main to set the log size to 50MB.
It should look something like
exec setuidgid svclog multilog t s52428800 ./main

You should update the root server list
wget -O - | grep ' A ' | tr -s ' ' | cut -d ' ' -f4 > /etc/dnscache/root/servers/\@

Update /etc/resolv.conf to use your new dns server.

Change UDP packet size to accommodate big UDP packets. Many DNS servers require large UDP packets or djbdnscache will fail with drop # input / output errors.



  1. Hello. If I might ask a question...

    When I tried step 3: Create the /etc/dnscache folder structure, using the command:
    sudo dnscache-conf dnscache svclog /etc/dnscache
    I got:
    sudo: dnscache-conf: command not found

    Any thoughts?

    Otherwise, THANKS for posting this! I spent a lot of time googling before I found this tutorial!

    1. Hello. dnscache-conf should have been included in the djbdns-1.05.tar.gz source archive found at

      I think it should have been installed when you did "make setup check" in the install instructions (after compiling the source).

      I suppose you could always run it from the build directory.

      Its been quite some time since I set it all up. Also, I recommend keeping djbdns logging to a minimum. It can be very noisy. I lost an SD card on a Pi once and I suspect that 6 months of noisy dns logs contributed to the card's failure.