KanREN DHCP Seminar November 7-9, 2005

Investigating Subnets and Fixed Addresses

You're plugged into the green network. You had an IP reservation on the yellow network—is that the IP you have now? Why not?

Create a reservation for yourself on the green network similar to the one you have on the yellow network. Note that in the current implementation, you can't have two host declarations with the same name, so you'll need to use a different name than you did before. Test the configuration, restart the server, refresh your client, and make sure you got the new reservation.

Isn't it annoying to have to double up host declarations to maintain multiple fixed addresses? Earlier versions of the server allowed multiple fixed-address declarations in the same host declaration, like this:

host neufeld-mac {

hardware ethernet 00:03:93:72:c1:d2;

fixed-address 192.168.11.100;

fixed-address 192.168.10.100;

}

But the current version doesn't.

Initially, we put the yellow subnet declaration in the main configuration file because it was the only network we were supporting. Do you like having on subnet defined in one file and the other in a different file? Why or why not?

Here's my answer: If a subnet has no clients and exists only to inform the server of its own network interface(s), I prefer to put it in the main configuration file. If a subnet has any clients, even if it's a subnet the server is attached to, I prefer to put them all together into the dhcpd.conf-subnets file.

Move your yellow subnet declaration from the main file to the subnets file, test and restart your server, and test that you still get the correct reserved IP address on each subnet.

2005-11-07T09:22:35