CISCO C3750X DHCP issue

Vladimir Bednikov · ‎05-30-2016

Hi All,

I have a CISCO C3750X switch which I have set up VLANs as well as tagging for a trunked port. That all works. I am also trying to set up two DHCP reservations and they are not working. The Windows PC is stating that there is limited connectivity and the IP address it got is completely different. The test PC is a Windows 2003 Server.

The commands I used were:

ip dhcp pool poo1

host 172.22.10.50 255.255.255.0

client-identifier 01UU.VVWW.XXYY.ZZ

I have also tried using hardware-address UUVV.WWXX.YYZZ to no avail.

show ip dhcp pool lists the pool and says 0 subnets is currently in the pool.

Anyone knows what is going on?

EDIT::

I then tried using port binding as according to the this article as follows:

ip dhcp relay information policy removal pad

no ip dhcp use vrf connected

ip dhcp use subscriber-id client-id

ip dhcp subscriber-id interface-name

ip dhcp pool testpool

network 172.22.10.0 255.255.255.0

address 172.22.10.50 client-id "Gi1/0/5" ascii

I am still not getting anything.

TIA,

Vlad

Philip D'Ath · ‎05-30-2016

The syntax needs to be like this:

ip dhcp pool nas
  host 192.168.1.252 255.255.255.0
  hardware-address 00d0.b821.9992

Vladimir Bednikov · ‎05-31-2016

Got it to work. The syntax is correct. However for layer three switches to issue dhcp addresses, the vlans must have an ip address. As soon as I assigned an IP address for the vlan in question, it worked.

However, what I want was to have two ports on that vlan to have DHCP. So with the following:

ip dhcp pool dantepciecards

network 172.22.10.0 255.255.255.0

default-router 172.22.10.1

lease infinite

address 172.22.10.50 client-id "Gi1/0/5" ascii

address 172.22.10.51 client-id "Gi1/0/14" ascii

It always assigns 51 no matter if I plug it into Gi1/0/5 or Gi1/0/14

It all works now. I forgot to release and renew the IP address. Once released, it got the new one when I swapped the ports. I wanted it to be port specific so if a piece of hardware fails, replacing it means that we don't have to reconfigure the switch for different MAC addresses