configure vpn 3000 to use dhcp to assign IP addresses

MARK BAKER · ‎05-18-2005

I have configured my VPN 3000 to assign IP addresses from a DHCP server, but it's not working. I see the DHCP discover packet go to the server but there is no reply from the server. I have an AS5300 that I configured to do the same on the same subnet as the VPN 3000 and it has no problem getting IP addresses from the DHCP server.

I did notice that the DHCP discover packet looked a little different between the VPN Concentrator and the AS5300, but am unsure why this would cause the Windows 2003 server to not provide a reply to the VPN Concentrators request.

Has anyone had an issue with the VPN 3000 receiving addresses from a Windows 2003 DHCP server?

I have just read a post where someone was wanting to stop using DHCP to assign IP addresses for VPN clients and was having trouble turning it off. I wish I knew what he was doing wrong.

Thanks for any help!

umedryk · ‎05-24-2005

I am not sure if this helps, but configuration is needed on both the server as well as the concentrator.

MARK BAKER · ‎05-24-2005

Turns out that the dhcp offer from the dhcp server is destined for the IP address listed as the "RELAY AGENT" in the dhcp discover packet and not to the same IP address used by the VPN concentrator to source the dhcp discover packet.

Since I expected the dhcp offer to go to the same address that sent the dhcp discover packet, the dhcp offer packet was not being allowed through our firewall.