Walkthrough

Relatively simple setup to enable a local DHCP server with dynamic DNS updates for a lab domain.

Tested and implemented on OpenBSD 5.1.

bash-4.2# uname -a

OpenBSD puffy 5.1 GENERIC#160 i386

bash-4.2# cat /etc/myname

puffy.lab.ttc

Instructions

The shipped DHCPD server does not support ddns so we must install the ISC-DHCPD one.

bash-4.2# pkg_add -r ftp://mirror.esc7.net/pub/OpenBSD/5.1/packages/i386/isc-dhcp-server-4.2.3.2.tgz

You can verify that you installed it.

bash-4.2# pkg_info -a

isc-dhcp-server-4.2.3.2 ISC DHCP Server

Create some additional NAMED files for logs.

bash-4.2# touch /var/named/named.run

bash-4.2# touch /var/named/named_query.log

bash-4.2# touch /var/named/named_dump.db

bash-4.2# chown named:named /var/named/named.run

bash-4.2# chown named:named /var/named/named_query.log

bash-4.2# chown named:named /var/named/named_dump.db

You will want to change the permission since we are running as user NAMED.

bash-4.2# chown named:named /var/named/master

bash-4.2# chgrp named /var/named/etc

bash-4.2# chown named:named /var/named/etc/*

Ensure your permissions for /var/named/ are correct. The following are what mine look like.

you may not have some of the db. files just yet.

bash-4.2# ls -l /var/named/

    drwxr-xr-x  2 root   wheel      512 Jul 12 07:21 dev

    drwxr-x---  2 root   named      512 Jul 11 10:59 etc

    drwxrwxr-x  2 named  named      512 Jul 13 06:26 master

    -rw-rw-r--  1 named  named  4564137 Jul 13 07:52 named.run

    -rw-rw-r--  1 named  named        0 Jul 12 07:31 named_dump.db

    -rw-rw-r--  1 named  named        0 Jul 12 07:31 named_query.log

    drwxrwxr-x  2 root   named      512 Feb 12 10:32 slave

    drwxr-xr-x  2 root   wheel      512 Jul 11 10:28 standard

    drwxrwxr-x  2 root   named      512 Feb 12 10:32 tmp

bash-4.2# ls -l /var/named/etc/

    -rw-r-----  1 named  named  1549 Jul 12 13:51 named.conf

    -rw-r-----  1 named  named    77 Jul 11 10:59 rndc.key

    -rw-r--r--  1 named  named  3110 Feb 12 10:32 root.hint

bash-4.2# ls -l /var/named/etc/master/

    -rw-r--r--  1 named  named   794 Jul 13 06:26 db.10.120.10

    -rw-r--r--  1 named  named  1478 Jul 13 06:26 db.lab.ttc

Edit your /etc/dhcpd.conf file. Use the one I've provided for reference/template.

Edit your /var/named/named.conf file. Use the one I've provided for reference/template.

Change the daemon in /etc/rc.d/dhcpd to point to /usr/local/sbin/dhcpd

I think this isn't the right way to do it since it may not stay during updates to the base os.

bash-4.2# sed -i 's/\/usr\/sbin\/dhcpd/\/usr\/local\/sbin\/dhcpd/' /etc/rc.d/dhcpd

Add both DHCPD and NAMED to your /etc/rc.conf.local file for startup.

bash-4.2# echo 'dhcpd_flags=""' >> /etc/rc.conf.local

bash-4.2# echo 'named_flags="-u named -d 3"' >> /etc/rc.conf.local

Now start both daemons. Hopefully they start...

bash-4.2# /etc/rc.d/dhcpd start

bash-4.2# /etc/rc.d/named start

Addendum

I've noticed two machines in my lab that never got a ddns record set during DHCP addressing. Apparently not all systems play nice with DHCP and don't send their hostname when they communicate with the server. You can manually force this on a linux machine.

Fedora 11: 
echo 'send host-name "fred";' >> /etc/dhclient-eth0.conf
Ubuntu 10.04: 
echo 'send host-name "barney";' >> /etc/dhcp3/dhclient.conf

Depending on distrobution and version you may have to look in different locations.

There may be cases were you are unable to send the hostname. You may force it within the dhcpd.conf file itself. Look at the dhcpd.conf file included for an example.

Questions/Comments/Priases can be sent to me at joe@unicornclouds.com