DHCP troubleshooting with 2 VLans on different subnets



I have windows 2000 server with DHCP serving two vlans

I have an extreme networks switch with a vlan for data & one for voice. The
dhcp server is on the data vlan and all data clients can get leases from the
dhcp server.

I have ip forwarding & bootprelay configured on the switch and I can ping
the server from the voice vlan and from the server to the voice vlan. But
when I try and pull a ipaddress with DHCP it errors out with DHCP Server
unreachable error.

How can I trouble shoot whether the request is being recieved by DHCP and
not serviced due to config issues in my scope vs a problem with the switch
not relaying the request?

Thanks for any help

Achint Setia {MSFT}

Just install Network Monitor or any other network sniffer on the server. See
if the server is receiving packets(DHCP DISCOVER) from the voice VLAN
clients(via the bootp relayagent installed on the switch). The server should
send back a DHCP OFFER back to the clients if it is willing to give some

If you have problems with sniffer, just disable the route to the server
from data VLAN. Stop and restart the server.
After doing a renew on the voice VLAN clients, see the server statistics
(Action->Display Statistics) if it received any discovers and sent any

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