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Frequent Contributor


I can get my dhcp server to see my phones, the server is in vlan1 the phones are in 200, we have about 10 switches, 1 server, 9 clients. Do I just need to enable ip routing on the core switch ?

please help


for some reason dhcp can give any pc an ip address in both vlans, but yet i cant ping the dhcp server when its on vlan 200, i dont understand !!

If I have a default gateway, and its got an ip address for the pc's in vlan 1, and also an ip for the pc's in vlan 200, would this make the vlans see each other by any chance ? I have not got intervlan routing set up, and dont want it set up. could this be causing them to see each other ?

please help .im stuck

Sorry, I must correct myeslf, I dont want the vlans to see each other, I put in the first post that I wanted vlan routing but I dontl I need them seperate !!

I know you're stressing, but you have to calm down and start breaking down your problem into solvable chunks.

Your vlans are going to see nothing of each other if you don't want them too. They will see the other subnet however(which is your vlan) once it hits the routers interface. If you don't want them seeing each other, then you need to look at some kind of access list or something.

You need to calmly break down what you want from us, give us exactly what you are trying to accomplish. It takes a few minutes, but it will save you much time later and you will get a usable answer that much faster.


The setup I want is

vlan1 , all pcs

vlan200, voIP phones

pc's are on a flat 10 address

phones are on 10.81.123.x class c address

They should be getting this address from a dhcp server plugged into the vlan 200 switch.

The default gateway has got the flat 10 ip and also a 10.81.123.x ip assigned to it. I think its this thats causing the dhcp server thats plugged into vlan200 to give out addresses to the pc's and phones whereas I only want the phones to have it !!!!


From what you have here this DHCP server will service all on the the VoIP Phones only and not the PCs. Now since your VoIP phones are on the same VLAN200 as the DHCP Server you probably don't need the "ip helper-address" command on the VLAN200 logical interface.

Can you be specific where this default gateway is configured ? Is it on DHCP Server, on VLAN200 or on VLAN1 ? Can you give samples ?

Also, when you say flat network 10 does that means VLAN1 is a class A network ?

Confirm on your logical interfaces VLAN1 and VLAN200 you have configured your default route on each of the VLANs logical interfaces and then using a static route entry or dynamic routing to route between your VLANs (Inter-VLAN routing).

I would like default gateway configured on default router if possible, the gateway to the dhcp server would be this !! Vlan 1 pc's are all on a address, the phones are on a 10.81.123.x address, I want to keep the traffic seperate ?


The default gateway for the dhcp server at the moment is on the main router which is the router also for vlan 1, and yes vlan 1 is on a address. !!!!

Can anyone help me solve this ?

cheers guys