Difference between revisions of "Cisco weird interfaces"

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(Created page with "= NVI - NAT Virtual Interface = Not everyone knows that from IOS version 12.3(14)T, Cisco has introduced a new feature called NAT Virtual Interface; NVI removes the requireme...")
 
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  R1(config)#ip nat source static 172.16.0.6 10.16.0.5
  R1(config)#ip nat source static 172.16.0.6 10.16.0.5


To better understand this feature, I will explain NVI using the same examples presented in the previous article ‘NAT and PAT: a complete explanation‘ (take no notice of the ip NAT inside/ouside in the images).
;References
 
*[http://www.ciscozine.com/2013/02/28/nat-virtual-interface-aka-nvi-what-is-that/ NAT Virtual Interface aka NVI, what is that?!]
First of all, define which interfaces will take part in the IP translation; in these scenarios will be fastethernet 0/0 and fastethernet 0/1:
 
R1(config)#interface range fastEthernet 0/0 -1
R1(config-if-range)#ip nat enable
 
Then define the translation depending on the NAT/PAT used.

Revision as of 13:11, 20 October 2013

NVI - NAT Virtual Interface

Not everyone knows that from IOS version 12.3(14)T, Cisco has introduced a new feature called NAT Virtual Interface; NVI removes the requirements to configure an interface as either NAT inside or NAT outside. An interface can be configured to use NAT or not use NAT.

How to use NVI? It’s easy! You must use the command ‘ip nat source …’ without specifying the inside/outside tag and enable the nat to the interfaces using the command ‘ip nat enable’.

For instance, if you use legacy statement:

R1(config)#interface range fastEthernet 0/0
R1(config-if-range)#ip nat inside
R1(config)#interface range fastEthernet 0/1
R1(config-if-range)#ip nat outside
R1(config)#ip nat inside source static 172.16.0.6 10.16.0.5

with NVI feature the nat will be:

R1(config)#interface range fastEthernet 0/0
R1(config-if-range)#ip nat enable
R1(config)#interface range fastEthernet 0/1
R1(config-if-range)#ip nat enable
R1(config)#ip nat source static 172.16.0.6 10.16.0.5
References