DHCP for ephone without voice vlan

Unanswered Question
Jul 29th, 2010
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Hi all!

Somebody knows a way to have two DHCP servers, one for PCs, and one for ephones on the same network?

I need to install an UC520 in a network with switchs and access-point that doesn't support VLANs. And in this network there are a DHCP server for Active Directory.

Or, if someone knows another way to solve this situation, please help me.


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Steven Holl Thu, 07/29/2010 - 09:18
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You don't want to have two DHCP servers in the same L2 broadcast domain (VLAN) because it will create a race confition on which server is able to answer the request first.

There is no need ot have two DHCP servers.  Since you already have a DHCP server running on a Windows server, just use that.  An IOS DHCP server doesn't provide anything that the Windows DHCP server can't do.  You just need to add an option 150 statement to the existing DHCP server configuration, to specify the TFTP server for CME/CUCM to whatever DHCP server you choose to use for offering addresses to the IP phones.

Your best bet is to leave all devices (PCs and phones) on the same flat network, and just add option 150 to whatever server you are already using for your existing data network.



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