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Why is NVI0 interface shutdown on Cisco 877-M

I've a Cisco 877-M router, just wondering why does the NVI0 interface always remain in shutdown state. I've just configured the router and not plugged in the ADSL link. Upon show ip int brief, NVI shows administratively shutdown. Any reason ?

LANm0nk3y

I believe this is the interface for NAT.
http://www.cisco.com/en/US/docs/ios/12_3t/12_3t14/feature/guide/gtnatvi.html

nabeel92

ASKER

hmm...yeah, but it doesnt explain why the interface would be in shutdown state ...

LANm0nk3y

I don't think you need it up to make NAT work. I just set up an 1811, and it's not up. It's just a virtual interface that cisco probably use so that the IP translation can happen.

LANm0nk3y

This is from the same document i just sent you:

The NAT Virtual Interface (NVI) feature removes the requirement to configure an interface as either Network Address Translation (NAT) inside or NAT outside. An interface can be configured to use NAT or not use NAT. 
 
NVI allows traffic between overlapped VPN routing/forwarding (VRFs) in the same Provider Edge (PE) router, and traffic from inside to inside between overlapping networks. 
 
History for the NAT Virtual Interface Feature

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JFrederick29

The NAT Virtual Interface (NVI) will be down until you configure NAT using the NVI method "ip nat enable". This is normal.

nabeel92

ASKER

Thanks.
So do I need to issue "Ip nat enable" command or just the router as it is.

Currently, the NAT related commands on the router are

interface vlan 1
ip nat inside

interfave dialer1
ip nat outside

ip nat inside source list 101 interface dialer1 overload
access-list 101 permit ip any any

LANm0nk3y

It's better if you show the sh run. Without seeinng interfaces it's a little harder to do this. the VLAN1 interface does not look correct.

nabeel92

ASKER

GG-MelbRtr1#sh running-config
Building configuration...

Current configuration : 2170 bytes
!
version 12.4
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname GG-MelbRtr1
!
boot-start-marker
boot-end-marker
!
no logging console
!
no aaa new-model
!
!
dot11 syslog
ip cef
!
!
ip name-server 139.130.4.4
!
!
!
username admin privilege 15 password 0 xxx
!
!
archive
log config
hidekeys
!
!
!
track 1 rtr 1 reachability
!
track 2 rtr 2 reachability
!
track 3 list boolean or
object 1
object 2
!
!
!
interface ATM0
no ip address
no atm ilmi-keepalive
pvc 8/35
encapsulation aal5mux ppp dialer
dialer pool-member 1
!
dsl operating-mode auto
!
interface FastEthernet0
!
interface FastEthernet1
!
interface FastEthernet2
!
interface FastEthernet3
!
interface Vlan1
ip address 10.153.25.121 255.255.255.128
ip nat inside
ip virtual-reassembly
glbp 1 ip 10.153.25.126
glbp 1 preempt delay minimum 30
glbp 1 weighting 100 lower 95
glbp 1 load-balancing host-dependent
glbp 1 weighting track 3 decrement 10
glbp 1 forwarder preempt delay minimum 0
!
interface Dialer1
description -- ADSL to Telstra --
bandwidth 1000
ip address negotiated
ip mtu 1440
ip flow ingress
ip flow egress
ip nat outside
no ip virtual-reassembly
encapsulation ppp
ip route-cache flow
dialer pool 1
dialer idle-timeout 0
dialer persistent
dialer-group 1
ppp authentication chap callin
ppp chap hostname xxx
ppp chap password 0 xxx
ppp ipcp dns request
ppp ipcp route default
!
ip forward-protocol nd
ip route 0.0.0.0 0.0.0.0 Dialer1
ip route 10.153.25.0 255.255.255.128 10.150.7.101
!
no ip http server
no ip http secure-server
ip nat inside source list 101 interface Dialer1 overload
ip nat inside source static tcp 10.150.7.101 22 interface Dialer1 222
!
ip sla 1
icmp-echo 4.2.2.2 source-interface Vlan1
frequency 10
ip sla schedule 1 life forever start-time now
ip sla 2
icmp-echo 4.2.2.3 source-interface Vlan1
frequency 10
ip sla schedule 2 life forever start-time now
access-list 101 permit ip any any
!
!
!
control-plane
!
!
line con 0
no modem enable
line aux 0
line vty 0 4
login local
!
scheduler max-task-time 5000
end

LANm0nk3y

Hmm... I wonder if it's because you have "no ip virtual-reassembly" As far as your nat config, it looks ok. I think you need ip virtual-reassembly on the dialer1 interface.

nabeel92

ASKER

just enabled it, didnt made a difference !

LANm0nk3y

what shows up if you do:

sh ip int br

nabeel92

ASKER

Interface IP-Address OK? Method Status Protocol
FastEthernet0 unassigned YES unset up down
FastEthernet1 unassigned YES unset up down
FastEthernet2 unassigned YES unset up down
FastEthernet3 unassigned YES unset up down
ATM0 unassigned YES NVRAM initializing down
Vlan1 10.153.25.122 YES NVRAM up down
NVI0 unassigned YES unset administratively down down
Dialer1 unassigned YES NVRAM up up
Virtual-Access1 unassigned YES unset up up

nabeel92

ASKER

Well I've configured everything correctly that i know for sure ... And usually when ADSL line is connected to the router, a new virtual-interface by the name of "Virtual-access 2" comes up which usually gets the Dialer I.P address. But i was just curious as to why this particular interface would be donw ?

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JFrederick29

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nabeel92

ASKER

Ohh ok ......

LANm0nk3y

I'm so sorry, I thought you were having problem with the internet or something. So sorry.

Runnex

Hi Sir,

Good day to you. Mine also have this NVI0 interface was in administrative down. May i know how to bring it up. Actually i am restore the old cisco 887 router config to new cisco 887 router. but in the show ip int brief of the old router, this nvi0 interface is up. so i believe the new router not function well due to this interface (administrative down). Thanks Please help...(URGENT)