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New Member

Basic connectivity to 871 router not working...

Trying to do a basic config with a Cisco 871 with IOS c870-advsecurityk9-mz.124-24.T4.bin. Connecting to ISP via DHCP. I get an IP from the ISP and can ping the ISP gateway from the WAN interface. My internal computer receives an IP from the 871 and can ping the ISP gateway as well, but that's as far as the traffic goes. I must be missing something in my config....Any suggestions? I think it is either a NAT, or ACL issue...

no service pad

service timestamps debug datetime msec

service timestamps log datetime msec

service password-encryption

hostname xxxx


boot system flash:c870-advsecurityk9-mz.124-24.T4.bin


logging message-counter syslog

enable secret

no aaa new-model

dot11 syslog

ip source-route

ip dhcp excluded-address

ip dhcp pool vlan1pool

   import all




ip cef

no ip domain lookup

ip domain name xxxxx


log config


interface Loopback0

no ip address

interface FastEthernet0

interface FastEthernet1

interface FastEthernet2

interface FastEthernet3

interface FastEthernet4

ip address dhcp
ip nat outside
ip virtual-reassembly
duplex auto
speed auto

interface Vlan1

ip address
ip nat inside
ip virtual-reassembly

ip forward-protocol nd

ip route FastEthernet4

no ip http server

no ip http secure-server

ip nat inside source list 1 interface FastEthernet4 overload

access-list 1 permit


Cisco Employee

Re: Basic connectivity to 871 router not working...

looks like your missing a default route.

ip route dhcp

New Member

Re: Basic connectivity to 871 router not working...

I thought this was covered by  the ip route

New Member

Re: Basic connectivity to 871 router not working...

Just tested by removing old default route and added the dhcp designation:

ip route dhcp

Its working now. I've never configured a default route that way before, but I don't work on the 871s much...

Thanks for the answer .


Re: Basic connectivity to 871 router not working...


You were already receiving a default route from your ISP with dhcp( installing a default static route with an AD of 254)  so just removing your static default route command should do the trick, because here you were overriding this route with one with a better AD but your  new default static route was pointing to the interface which was fastethernet and so if the ISP gateway was not configured for proxy arp( and it shouldn't be) then it won't work but if you had pointed towards next hop( ISP gateway) it should have worked.


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