Traffic not routing from lan to wan

[ahardin1990]

So I got a 3925 router. Configured G0/0 for the cable modem. And configured G0/1 for my lan. The issue I’m having is I can ping google from the router but when I connect my laptop to the G0/1 port I cannot ping google. So for some reason the traffic from G0/1 is not being routed to the internet through G0/0. I have read countless posts and have tried many many things this is driving me crazy. 

[balaji.bandi]

can you post-show run from the router, Looks to me high-level NAT issue.

high-level config should look like below :  (if you are not doing NAT on this router, then uplink cable mode need to be done the same and route back your lan IP addres range towards 3925 router from cable modem)

interface GigabitEthernet0/0
ip nat outside
!
interface GigabitEthernet0/1
ip nat inside (this is just example, if you using vlan then this config go to VLAN)
!
ip nat inside source list 1 interface GigabitEthernet0/0 overload
!
ip route 0.0.0.0 0.0.0.0 GigabitEthernet0/0 or uplink cable modem IP
!
access-list 1 permit 192.168.1.0 0.0.0.255 (chang ethis LAN IP address range)
!

[ahardin1990]

Sorry I have to use pics as I’m working off my iPad as I cannot get my pic online

[balaji.bandi]

Try the below changes : ( did PC get Lan ip range from DHCP ?)

no ip nat inside source list My_LAN interface GigabitEthernet0/0 overload
ip nat inside source list 1 interface GigabitEthernet0/0 overload
!
mo ip route 0.0.0.0 0.0.0.0 GigabitEthernet0/0
ip route 0.0.0.0 0.0.0.0 GigabitEthernet0/0 dhcp
!
access-list 1 permit 192.168.1.0 0.0.0.255

let me know how the test go. once change the config (still not working, post again new config)

[ahardin1990]

I can now ping the address that the cable modem gave to int G0/0 from pc but not google. Router can still ping google.

[balaji.bandi · Accepted solution]

i see below command in the config 

no ip routing.

change this to 

ip routing

test it, still issue post

show run

again.

[ahardin1990]

 You are a genius the ip routing was the answer

[Joseph W. Doherty]

Yup, to route packets, you need to insure routing is enabled.

Interesting, though, I recall (?) the default is IP routing is enabled on 39xx ISRs (since the expectation is for a router to route - many L3 switches, though, I recall [?] have IP routing disabled by default).

BTW, it also appears CEF is disabled.  Generally, the recommendation is, when routing, to have it enabled.

[ahardin1990]

When I got it I erased the nvram and performed factory reset. So it is strange that that would be disabled. I can’t believe I missed that. What a noob move. You my friend are a life saver as I was driving myself insane with the issue. Everything is running awesome now. After I followed your fix I was able then to set up my radius server as I use WPA3 Enterprise on my WAPS. I will go back and enable the CEF as you pointed out. I’ve been out of the networking realm for about 12 years. I have forgotten a good bit. Thanks again for your assistance.

[ahardin1990]