Splitting DHCP between workstations and phones

[Marcell]

Hello to all

We want to be able to split our dhcp to assign different IP address's to workstations and to phones. We currently have 1 dhcp scope running on windows server 2003 on our DC. We have another server (win2003) on which the shoretel software is installed and which the phones connect to via ftp to download their cfg. We run the Shoretel 6.1 system with 2 x shoretel switches for approximately 70 phones.

I have done some reading within this helpful forum, and the majority of suggestions on doing this revolve around using VLans, but this is something we would like to avoid as to be honest, we dont have a huge amount of VLan experience here. We were thinking of turning our Shoretel server into a virtual machine, but were told that Shoretel would not support us if we ran the app on a VM.

Can someone give me guidance on how to acheive the dhcp split using a single DC and a single scope (obviously we will need to create another?)

Let me know what other info you require as im sure i probably didnt give everything needed, first post on this forum and only been admin on this system for a short time.

Many thanks

Marcell

[ShoreTel_Dave]

VLAN's are not all that complicated!

You can only have one DHCP server on a subnet. DHCP requests are broadcast over the whole subnet by the client and the server will initially respond with a broadcast reply. There would be no way to get the DHCP server to figure out whether the client was a PC or a Phone (though in theory if you were able to tell the DHCP server that things with a mac address beginning 00:10:49:xx:xx:xx were phones you would have some more options but that isn't possible with Microsoft DHCP as far as I am aware)

The only way I can think of being able to specify the IP addresses to phones without creating a voice vlan would be to use reservations.
You would need to make a list of all the mac addresses on the phones and then add them one by one to DHCP, specifying the IP address (which needs to fall within the scope) for each device.
If you are good with a batch file, you could save yourself some effort by using Excel and the command line tool "netsh" on the DHCP server to add the reservations en-mass.

However, it would probably be less effort in the long term to create a new voice vlan, tag all the edge ports on the network, set up a bootp forwarder or dhcp relay on the network switch and add a new scope to DHCP. DHCP will figure out that the request came from the voice vlan and issue an appropriate address.

As a ShoreTel customer you would not be required to understand the ins and outs of setting up Vlans on your network. As an implementation engineer, I do this kind of thing all the time and I would either set these up for you if I was familiar with your switch vendor, or call in a contractor for a day who is. I found it is usually cheaper to pay an expert in their particular field that to spend days and days trying to do it myself.

Finally, don't turn your ShoreTel server into a virtual machine just at the moment. (this doesn't have anything to do with vlans and DHCP anyway)