04-16-2012 04:42 PM - edited 03-07-2019 06:09 AM
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
04-16-2012 04:52 PM
Kindly post the output to the command "sh run interface fast0/0"?
04-16-2012 04:57 PM
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
04-16-2012 05:08 PM
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
04-16-2012 05:15 PM
everything wokrs fine for the most part, but I can't ping that IP from anywhere inside outside .. even from within the router itself..
04-16-2012 05:33 PM
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
04-16-2012 05:45 PM
Hey Jan,
I'm not configuring the NVI nat, but IP NAT inside and outside..
Thank you
04-16-2012 05:52 PM
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
04-16-2012 06:00 PM
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 .
04-16-2012 06:29 PM
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
04-16-2012 06:38 PM
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..
04-16-2012 06:46 PM
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
04-16-2012 06:52 PM
I deleted my post after seeing that you had it fixed already Are you having any other issues still?
04-16-2012 07:05 PM
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 ?
04-16-2012 07:11 PM
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?
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