How to reference dynamic IP with named DNS

[Brian Gaynor]

On Wed, 2005-04-20 at 15:27 +1000, Neil Dugan wrote:
> I have a local network with a couple of server computers setup with
> static IP addresses.  I also have 2 computers with dynamic IP addresses
> gotten though DHCP.  Using 'named' as a DNS I can access the 2 server
> computers via names.  But I haven't been able to figure out how to be
> able to access the computers with dynamic IP address via a name.  I can
> access them fine with there IP address.

This is easy if as long as one of the Fedora servers is also the DHCP
server. It may not be possible if your DHCP server is a consumer grade
appliance (e.g. a wireless router box) as these devices cannot typically
be configured to send the notifications as far as I know. You need to
configure the DHCP daemon to do dynamic updates - add the following to
the top of /etc/dhcpd.conf:

    ddns-update-style interim;
    ddns-updates on;

Assuming the DHCP server is on the same machine as named, you need to
add "allow-update { localhost; };" to the appropriate zone sections
in /etc/named.conf. For example:

zone "1.168.192.in-addr.arpa" {
    type master;
    file "1.168.192.in-addr.arpa.zone";
    allow-update { localhost; };
};

zone "mydomain.com" {
    type master;
    file "mydomain.com.zone";
    allow-update { localhost; };
};

-- 
Brian Gaynor
www.pmccorp.com
FC3/Linux on DELL Inspiron 5160 3.0Ghz 
canis 22:42:04 up 27 min, 2 
users, load average: 0.28, 0.29,