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AT&T 3800HGV RG, Static IP and multiple Cisco Routers

I've got a block of 8 static IPs, one A.B.C.64 /29 - A.B.C.70 is my  default gateway, my Cisco E2000 router runs my main home LAN and is  doing just fine. I am using two of the RG's ports to run my U-verse  set-top boxes via Ethernet, one for the WAN link on the E2000 and one  goes to a 4-port DLink switch that then goes to a Cisco 2621XM.  Everythings works super except the 2621... I have fa0/1 setup to  A.B.C.66 (the E2000 is .65, btw) and I have fa0/0 set to 172.16.1.1 /24  and one PC connected to it set to 172.16.1.10 /24 with a default gateway  of 172.16.1.1. I can ping A.B.C.70 from the 2621 just fine and I can  ping an outside address such as Google, Apple, etc just fine. What is  puzzling me to no end is why I CAN ping A.B.C.66 from the PC, but I  CANNOT ping A.B.C.70???? What the heck, it's a directly connected  interface; I cannot for the life of me understand this. The only thing I  can come up with is that somehow the RG is not setting up a return  route.

I tried this before with and without NAT, same result, this current config has NAT turned on.
I am a novice so it is quite likely I have something setup wrong.
For instance, it seems redundant to have both a default gateway to xxx.xxx.xxx.70 and also a quad-zero route,
but I tried it just to see if it fixed it and haven't turned the default gateway back off.
Another odd thing is that if I set up a quad-zero pointing directly to the fa0/1 it won't ping to the WAN,
Google, Apple, etc, I must use the 0.0.0.0 0.0.0.0 xxx.xxx.xxx.70, why is that?

Here's my current config:

Building configuration...

Current configuration : 823 bytes
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
!
memory-size iomem 10
no aaa new-model
ip subnet-zero
ip cef
!
!
!
!
!
!
!
!
interface FastEthernet0/0
ip address 172.16.1.1 255.255.255.0
duplex auto
speed auto
!
interface Serial0/0
no ip address
shutdown
!
interface FastEthernet0/1
ip address xxx.xxx.xxx.66 255.255.255.248
ip nat outside
duplex auto
speed auto
!
interface Serial0/1
no ip address
!
ip default-gateway xxx.xxx.xxx.70
ip nat inside source list 1 interface FastEthernet0/0 overload
ip http server
ip classless
ip route 0.0.0.0 0.0.0.0 xxx.xxx.xxx.70
!
!
access-list 1 permit 172.16.1.0 0.0.0.255
!
line con 0
logging synchronous
line aux 0
line vty 0 4
login
!
!
end

EDIT: I got it fixed, I had the NAT setup wrong, needed to have:

ip nat inside source list 1 interface FastEthernet0/1 overload

and "ip nat inside" for fa0/0

SomeJoe777 on the AT&T forums for the solution...

Message was edited by: Gary Britton

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