Hi,
Have recently installed a 4 switch Cat3750X stack for a Customer.
The stack is acting as distribution switch and server aggregation in their enterprise LAN.
Routing is enabled on the stack and there are a few diffrent VLAN's (server, client, print, wireless clients). A centralized DHCP server is placed on the server VLAN and the plan was to use IP Helper/DHCP relay on the client VLAN's.
But - the DHCP service is not working and I suspect some problem with the IP Helper funtionality on the 3750X stack.
The scenario is:
- The client send a DCHP broadcast
- The broadcast is received by the 3750 switch on the local interface with IP Helper enabled
- The switch sends a DHCP unicast to the server
- The server replies to the switch
... so far so good ..
- But the switch never sends the DHCP reply back to the client as a broadcast ....
Have attached an output from the DHCP debug on the 3750 where I can see f.ex:
Jun 19 12:00:31.490: DHCPD: Sending notification of ASSIGNMENT_FAILURE:
Jun 19 12:00:31.490: DHCPD: due to: CANT FORWARD
... so temporary we have to use the switch as a DHCP server (which is not wanted by the customer).
Some details:
- Have attached config for the stack
- Are using IOS 15.0.1-SE2 with IP base licence
