give out DHCP addresses based on mac address 2

[nath01]

im running 2k3 with AD and DHCP installed

i want to segragate our pcs from IP phones, is there any way to configure dhcp to only give out addresses in a range if the mac address begins with say 08-00-0f

i want to give the phones ips in the 100-200 range and pcs in the 1-100 part of a class c ip range. the thinking behind it is to have a clear devide between pcs/phones within the network.

is this posable?

Thanks for any help

 

[chipk]

If you knew the EXACT MAC addresses, you could create reservations for all your phones (or pcs) and just let the other take up the rest of the scope.

You can script this with the netsh command:

netsh dhcp server <scope>

Once you get to that netsh context, just do:

add reservedip ?

to see all the options.

The pc macs may be easiest to get by doing like a "net view" redirecting the output and then using "nbtstat -a \\computername" to get the mac address. You can do all this with for loops in a batch file in minimal time.

 

[nath01]

i dont patically want to use resevations as its very long winded to admin i want windows to give out ips based on the first 6 didgets of the mac address, i dont even know if this is posable!

 

[Grenage]

Hi Nath,

I know this is not what you asked for, but in your situation, would static IP addresses for the phones simply be a more efficient way of doing it?


Carlsberg don't run I.T departments, but if they did they'd probably be more fun.

 

[chipk]

Reservations are based on a complete MAC address. You can't do wildcards or partial addresses.

So, let's go back to the beginning. What exactly are you trying to accomplish? Are you worried about phones taking up bandwidth? Because on a LAN, this is generally not a concern. Even so, you could use QoS to prioritize voice/data traffic. If this is strictly for management purposes, then why not just subnet your class C into two subnets and have two separate scopes? One for voice, one for data.

What does your network look like? Do you have Cisco or other switches, hubs, how many segments, etc?

 

[dheida]

Don't know what platform you're on but we have a separate VLAN for our Cisco phones, which the Cisco switches can identify, allowing the DHCP server to give the phones a different range of IP's. I don't know exactly how it is implemented but I know that's how it behaves.

 

[PScottC]

MS DHCP server is not capable of handing out IP's based on a partial MAC address, sorry. What IP phones are you using. If you are using Cisco, there are quite a few people on this site who can help, including me.

The only way to separate the phones from the PC's is to do reservations for one set of devices (painful), or get the phones onto a separate subnet.


PSC

Governments and corporations need people like you and me. We are samurai. The keyboard cowboys. And all those other people out there who have no idea what's going on are the cattle. Mooo! --Mr. The Plague, from the movie "Hackers