I've predominately used Cisco and Enterasys, and for the life of me I cannot get this to work properly on an HP Pro Curve 2910al switch. The scope here: I've got a Windows 2003 DHCP server. IP address is 10.10.10.1. This server has two DHCP scopes - 10.10.10.0 (VLAN 10) and 10.10.100.0 (VLAN 100).
On the switch level, I have all ports set to use VLAN 10 untagged and VLAN 100 as tagged. I've setup both VLANs with ip-helper address of 10.10.10.1.
This is the setup for us to be able to daisy chain a PC behind a Phone, and have the two on separate networks (VLAN 10= data, VLAN100=Voice). Using a custom DHCP option, I can force the phone to turn on Layer 2 tagging and assign itself to VLAN 100.
So, when I attach the phone, it hits DHCP and takes an IP in the data range. It then see's it needs to change it's VLAN and goes through a network re-configure. It reboots and attempts DHCP (trying to get an address in VLAN 100). The phone never get's an IP.
Note: There is a default VLAN that I was using to stack the switches. I've cut back to using a single switch and changed the primary VLAN to VLAN10, which has done nothing.
What is the proper (port) setup to allow DHCP for both subnets?