asked on

Point Windows 7 to Specific DHCP Server?

I have DHCP setup on two different pieces of equipment in my current environment, not my choosing. Both scopes are on VLAN 1 with different ranges.

1) DHCP on a Windows 2008 R2 Server - For Virtual PCs (VMware View)
2) DHCP on a Cisco IOS Switch - Preboot for IP phones with options, which point them to reboot on the Voice VLAN

The IP Phones are having problems registering to the Windows 2008 R2 Server, hence the reason for using the Cisco Switch (according to the phone vendor).

The PCs keep pulling DHCP from the Cisco Switch, because it is responding first.

I know i can't do MAC filtering for DHCP on the Cisco Switch.

So, what are my other options?

Can I point my Windows 7 PCs to a specific DHCP server? If so, how?

Thank you Experts!

john15nlt

Its there a specific reason you have to use the the dhcp server off the Windows 2008 server. I have seen the issue you are speaking of in regards to the ip phones, but it seems the simple solution is to turn off the dhcp on the windows server.

Cliff Galiher

DHCP is a broadcast protocol and that is inherent in its design. You cannot "point" a client at a specific server... that'd defeat the purpose of DHCP. The only way to limit DHCP responses is to limit the broadcast domain (VLANs, routers, etc) or limit the server's responses via class/vendor/mac filtering or similar. It can't be done on the client end.

Will Szymkowski

As stated already there is no setting to accomplish this but what you can do is the following.
Example
Have your DHCP servers on VLAN1 have your workstations on VLAN2 and only assign a DHCP helper address on VLAN2 for the DHCP server you want your clients connecting to. If you do not add a helper address for the second DHCP server your clients will never use it.

This is just an example of how you can get around what your trying to accomplish. This is by no means a best practice because if that DHCP server goes down then all of your clients will no longer get leases and when their lease expires they will not be able to communicate on the network.

Will.

First Last

ASKER

Will -

Any idea on how i should configure the new VLAN 5 to point to VLAN 1 which is where the DHCP server is located?

I created the VLAN:
vlan 5
name ViewDesktops

interface Vlan5
no ip address
ip helper-address 10.35.208.70
end

I enabled the vlan 5

I assigned my switch port to the VLAN
interface GigabitEthernet10/9
switchport access vlan 5

ASKER CERTIFIED SOLUTION

Will Szymkowski

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

First Last

ASKER

Will - Great answer! Your solution would work, but not in my situation. It won't work for me because both VLANS need to have the same IP Range. So, i'm going to physically move everything from two different DHCP servers to one DHCP server and keep everything on one VLAN.