DHCP Issue on VLAN

[scottkrueger]

We recently moved a computer from one location to another within our plant.  We currently have trunked VLAN's going to multiple switches so we moved the computer plugged it into the nearest switch(3750 Stacked plugged into the Master (Member was full)) and I set the VLAN on the port.  I cannot get an IP address from our DHCP server. Now there are close to 50 other machines working on this switch with no issues.  This machine is a Windows 2000 machine, but I have tried plugging my notebook into it (Windows 7 Pro) and I don't get an address either.  Here is the config as it relates to that port:

interface FastEthernet2/0/14
description MIT Scope
switchport access vlan 82
switchport mode access
speed 100
spanning-tree portfast

Global information from Switch:

interface Vlan82
no ip address
ip helper-address 192.168.1.164   ---- This is our DHCP Server

ip default-gateway 192.168.0.1    ---- Main Switch where trunk originates
ip classless
ip route 0.0.0.0 0.0.0.0 192.168.0.2   ---- Router
ip http server

Thanks!

[Edison Ortiz · Accepted solution]

The IP-Helper command should be under the interface that has an IP address. If the switch is purely Layer2, you need to place the IP-Helper on the switch performing the intervlan routing. Since you mentioned other computers are getting an IP address from the same switch and same Vlan, have you checked that you have enough leases left on the DHCP scope?

Also, I don't recommend forcing the speed on an access port, it should be set to auto/auto.

Regards,

Edison

[scottkrueger]

Our main 3750 switch were we have the VLAN setup does have the ip helper

-address on each VLAN. We have plenty of addresses left in our scopes.  Is there anything with the Master/Member that I need to look at?

[Edison Ortiz]

Do you have devices on the same switch that are able to obtain an IP address from Vlan 82 on a different switchport?