I have a route-map that is supposed to direct all traffic entering an interface to route out the particular interface connected to our cable modem using NAT. The IP address on the cable modem (used as the NAT inside global IP) is DHCP assigned from the cable system. I don't really know what IP I will get, or what the default gateway is for that subnet. But the cable modem does have a statically assigned ip address 192.168.100.1. So I have been using that as the next-hop in the route map, as well as the next hop in the default route. I have a route statement for 192.168.100.1 directing it to the physical interface, and the modem does answer arp for that IP. Testing seems to show that the route-map is ignored, and the main routing table used instead of the next-hop, but if I manually add the IP address of the default gateway supplied from the cable system (from the DHCP response), then that next-hop is honored. This is only an issue for traffic that has a more-specific route (to a third interface) and wouldn't normally follow the default route without the action of the route-map (like net 10 below).
How can I get the 192.168.100.1 IPA in the cable modem to be accepted by the router/route-map as a valid adjacent next-hop? I've tried various combinations of static routes and subnet sizes. The arp table has the IP resolved, the sh adj command shows that IP too.
Thanks for any help or insights.
! interface FastEthernet0/0.12 description Cablevision (SB5100) lan segment encapsulation dot1Q 10 ip address dhcp client-id FastEthernet0/0 hostname JRCCV ip access-group cvrout1 out no ip redirects no ip unreachables no ip proxy-arp ip accounting access-violations ip nat outside ip nbar protocol-discovery no ip mroute-cache no snmp trap link-status no cdp enable ! ! route-map cvdhcpip permit 10 description policy to force all traffic out CV interface match ip address cvdhcp2 set ip next-hop 192.168.100.1 18.104.22.168