cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
1462
Views
10
Helpful
15
Replies

Is there anything wrong with this picture ?

love2xlr8
Level 1
Level 1

I was wondering why do i see the Public IP

108.177.99.174 on Fa0/0, and NVI0 at the same time ? The IP is only configured on fa0/0

router #sh ip int bri

Interface                  IP-Address      OK? Method Status                Prot

ocol

FastEthernet0/0            108.177.99.174   YES NVRAM  up                    up

FastEthernet0/1            unassigned      YES NVRAM  up                    up

FastEthernet0/1.1          172.22.1.1      YES NVRAM  up                    up

FastEthernet0/1.10         172.22.10.1     YES NVRAM  up                    up

FastEthernet0/1.100        172.22.100.1    YES NVRAM  up                    up

FastEthernet0/1.101        172.22.101.1    YES NVRAM  up                    up

Serial0/2/0                unassigned      YES NVRAM  administratively down down

NVI0                       108.177.99.174   YES unset  up                    up

15 Replies 15

Leo Laohoo
Hall of Fame
Hall of Fame

Kindly post the output to the command "sh run interface fast0/0"?

There you go::

interface FastEthernet0/0

description to ISP

ip address 108.177.99.174 255.255.255.248

ip nat outside

ip nat enable

ip virtual-reassembly

duplex auto

speed auto

end

Hi,

I think that everythink is just fine. NVI is just NAT virtual interface which is enabled for NAT purposes. The NVI takes the first IP address of the interface where the command ip nat enable is configured.

Best regards,

Jan

everything wokrs fine for the most part, but I can't ping that IP from anywhere inside outside .. even from within the router itself..

Hi,

what kind of NAT are you configuring? NAT with ip nat inside and ip nat outside commands or the NVI?

As far as I know there should be either the commands :

ip nat inside and ip nat outside commands

OR

ip nat enable command

But I see that you have also the ip nat enable configured on fa0/0 interface. Isn't that making any trouble?

If you are configuring the NVI please reffer to this guide:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t14/feature/guide/gtnatvi.html#wp1027188

Best regards,

Jan

Hey Jan,

I'm not configuring the NVI nat, but IP NAT inside and outside..

Thank you

Hi,

So what about the command ip nat enable? Can you try to clear it by no ip nat enable? If you don't have some production going on I'm not absolutely sure what it will cause...but I think it shouldn't be there unless you are configuring the NVI.

Best regards,

Jan

Jan,

I removed that statement, but it don't seem to make a difference.. I still can't ping that interface for the router itself .

Hi,

this is an strange problem indeed. I am trying to simulate it in GNS3, what kind of device do you use? Maybe it is because of the NVI getting the same IP, but I am not able to replicate this scenario right now. I will inform you as soon as I find something out...maybe someone will get to the root of the problem by that time, but anyway, I will try to solve the issue in the meantime. Everything else is ok so far? Only the ping from the router on the interface won't work, is that right?

Best regards,

Jan

Jan,

Thanks _ I greatly appreciate your assistance... As i said everything is working for the most part, NAT traffic is going in and out however I do have some issue with my CME which i think is related to this issue..

J.

Plase see attached the config file, I have modified the Public IP's since this is a public forum,everything else is untouched..

Thx

Edit: Someone with name J. posted asking for the config, but he deleted his post for some reason.. I'll leave the configs in case he decides to take a look

Message was edited by: love2xlr8

I deleted my post after seeing that you had it fixed already Are you having any other issues still?

HTH, John *** Please rate all useful posts ***

J.

I'm troubleshooting some CME issues, but i believe its all tied together..

Nat and everything works well, but I can't ping anything outside from this router, even its own WAN interface.. Shouldn't I be able to ?

Is this in production? If not, try to remove your outside static nats to see if you can ping. You can also try to ping out sourcing from one of your inside addresses. You should be able to ping your gateway from the router. Are there any other devices involved?

HTH, John *** Please rate all useful posts ***
Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Innovations in Cisco Full Stack Observability - A new webinar from Cisco