Cannot ping from router.

[Jeremy Tyson]

Recently just attempted to setup my 1800 series router with charter cable internet. Everything seems to be set up correctly but we can't ping anything outside of our local network.  I'm just curious what the first step to take in resolving this is. I have posted a copy of my running config if anyone would like to help.

Thanks, Jeremy

[mohammed asif suleman]

It depends upon what ip you are getting on to your cisco router,if you are getting public ip to your cisco router from charter modem, then you can go with the config John Blakley gave you.

as per your roommate's suggestion there will be no difference placing a non manageable switch anywhere.

[Jeremy Tyson]

I believe the "ip route 0.0.0.0 0.0.0.0 71.82.222.1 254" was something that was configured automatically by the cisco router. After connecting my cisco router to a port on the back of my consumer linksys router (roommates were getting sick of me stealing the internet lol),  I now have "ip route 0.0.0.0 0.0.0.0 192.168.1.1 254" in its place. I'm curious why the 254 is there and why the gateway needs a subnet mask?

[John Blakley]

You shouldn't be receiving a default route pointing to 192.168.1.1 unless your Linksys is handing out dhcp. If that's the case, that means that your WAN interface is getting a 192.168.1.x address from the Linksys and you're double natting.

How do you want this laid out? I was under the impression that you had the cable/dsl modem connected directly to the router. Is that not the case? Are they needing the Linksys for wireless? It would be easier to reverse your logic if that's the case.

How I would do it is connect your modem to the Cisco router, and then connect the Linksys wan port to the lan port on the router. Then you can hand out dhcp on the Linksys and not have to nat. Your default gateway on the Linksys would point to the Cisco router, and your default route on the Cisco would point to the provider.

[Jeremy Tyson]

For the sake of being able to disconnect and move my lab around or still be able to change the configuration according to homework handed out by my teacher without affecting everyone else's internet connection (6 roommates), I want to connect it as follows. Charter Modem --> Linksys consumer router --> Cisco router --> Cisco switch.  When I initially was working with you, I was disconnecting the linksys router from the Charter modem so I could connect the Cisco router in its place which was interrupting everyone else's internet access.

[mohammed asif suleman]

by looking at your config it seems you are sending your local traffic over the WAN interface and denying all other traffic

please can you check by changing the access-list

access-list 101 deny ip any 192.168.0.0 0.0.0.255

access-list 101 permit ip any any

[Jeremy Tyson]

This is what the problem was. Thank you so much. Can you briefly explain why this fixed it? Also does this mean after configuring the switch, will I simply be able to plug the router directly into the switch and assuming the switch is configured correctly, it should work? Or do I have it configured in such a way to only work with a host directly connected?

[John Blakley]

Jeremy,

I'm very confused at this point. In your initial configuration you sent, you have absolutely no acl applied to any interface. The acl that you had is configured for nat only, and it was configured correctly. I simply cannot see how the above answer resolved your question considering that the only way the above would work is if you were trying to go from any subnet to 192.168.0.0/24 and not wanting to nat. You always should tie your local subnets specifically to your nat config. I would absolutely never suggest using "permit ip any any" in an acl that's tied to your nat config. Are you sure the above resolved your issue? I don't see how...

John

[Jeremy Tyson]

I'm absolutely certain that after changing my config to what he specified made it work. I don't have the necessary knowledge to explain how but I know that made it work. I have since gone over the config again according to what you specified below and it still works.