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Cisco 3620 and Internet access

raymondwrio
Beginner
Beginner

I have a Cisco 3620 router and I am trying to get internet access. My isp is comcast. All modem lights seem to be operational. But I do not have internet access. I can ping anything other then the router and I am on a home network.

I have attached a config file. Please note I am a novice with cisco routers.

47 REPLIES 47

Hi Ray,

mac-address 000b.46cc.8fc1     (This is the mac addr of the E0/0 interface card)

no need to put this command on eth0/0 as it is already its MAC address and furthermore this interface is not connected to the modem.It won't do any bad  but it is unnecessary.

no ip route-cache

Don't enter this command, renable it with either ip cef global command or ip route-cache cef interface command and verify with sh cef interface command.

Your arp requests for the PC gateway( 192.168.3.1) are not replied by the router, can you try to purge the cache with arp -d * command on the PC and do a ping 192.168.3.1 and then see if you get the correct mapping in the cache.

But I would like to have the wireshark capture when PC connected directly to modem.

Regards.

Alain

Don't forget to rate helpful posts.

I removed the mac address from E0/0. And removed the no ip route.

(Note that "no ip route-cache" and "ip address dhcp" commands were added from the Cisco config link from about. That's why they were in the config.)

New wireshark file add. Info captured while pc was connected to the cable modem this time, and all pings were fine.

And updated config file attached also. I could not remove the " no ip mroute-cache" command.

Thanks Ray

Hi Ray,

Why did you remove the ip address dhcp command on eth0/1 ? reenter this command

if you don't get the default-gateway ( sh ip route) then try this :

ip route 0.0.0.0 0.0.0.0 dhcp

let us know.

Regards.

Alain


Don't forget to rate helpful posts.

ebarticel
Enthusiast
Enthusiast

Hi Ray,

I just want to add something else to all the good advise you get from Alain.

This things needs to be performed in certain order, otherwise it won't work.

After you have changed mac address on router to match the mac on pc, and before you connect router to modem, make sure that you use a pin to reset modem to factory defaults, should have a small opening at the back.

After the modem is reset to factory defaults, plug in the router and no PC connected to router.

Eugen

Made all corrections, reset modem to defaults and still no internet.

Ran (sh ip route) and only e0/0 is returned. Pinged to router from pc is fine but ping 8.8.8.8 says no destination,(ping 8.8.8.8 from both pc and router).

When I tried to run (ip route 0.0.0.0 0.0.0.0 dhcp) it return, "Invalid input detected at dhcp". When I run

ip route 0.0.0.0 0.0.0.0 ?, there is no dhcp option.

Ray