I have a lab setup to help me take my CCNA and CCNP and Im having issues trying to get WAN connectivity back to a swictch at the end of my network. My lab envoirnment consists of 1 - 2950 switch, 1 - 2620 and 1 - 2621XM. I have 1 ethernet connection from each router to the switch and 1 serial connection from the 2620 to the 2621XM. I have the serial interfaces in a shutdown state right now so there is no loop since I do not have Spanning tree setup on the ports on the swtich yet. Right now using the fastethernet ports on the routers and I have no issues its when I shutdownt those ethernet ports and try using the serial interfaces when I start having issues. So my network layout is ethernet from switch port f0/4 to port f0/0 on 2620 and serial from s0/1 on the 2620 to s0/2 on the 2621XM. My 2621XM f0/1 is whats connected to the WAN and I have no issues getting to the WAN from my 2621Xm or my 2620 but when I try pinging any website or even my WAN default gateway from my switch I get nothing! Ive also noticed that when I do a IP NAT translation (after accessing the WAN from my 2620) on my 2621XM the source IP is of my serial connection not the ip of my 2620 router? I have my default gateway on the 2620 as the the IP of my serial interface on the 2621XM and visa versa because my LAN network is 172.16.1.0 and my WAN is 172.16.9.0. I have a /31 setup between my serial connections 172.16.11.0 (s0/1) is on the 2620 and 172.16.11.1(s0/2) is on the 2621XM. I used the SDM (ver 2.5) to setup NAT to have f0/1 with nat outside and s0/2 as nat inside. Encapsulation is HDLC between the serial links. Ive attached the running configs of the swtich and routers. Any help would be greatly appreciated!
