NAT query..

Unanswered Question
Jul 2nd, 2007
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I have router Cisco 1841 on which I have two internet links. I have configured following two commands on it:

ip nat inside source list 101 interface FastEthernet0/0 overload

ip nat inside source static interface FastEthernet0/0

I want to configure the same above commands for one more interface which is fastethernet 0/1. is the ip address of a device which is directly connected to 1841 with vlan1 interface.

Can I do this somehow? I tried but I could not. But I have seen it on 3845 router that it can be configured. IOS version of both routers is 12.4.

I would highly appreciate anyone's prompt help. Thanks.

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Overall Rating: 4 (1 ratings)
paolo bevilacqua Mon, 07/02/2007 - 08:55
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If you configure that for FA0/1 too, that assumes that said interface is outside too.

Is that what you want? Do you want to go out via FA0/1 ? You need PBR for that.

royalblues Mon, 07/02/2007 - 10:13
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If i understand, you require the source to be natted to 2 different IPs when it leaves the router, i.e nat it to fa 0/0 when the destination is bound that interface and nat to fa0/1 when leaving from that interface

If this is the requirement you would require NAT with route maps.

When you create a NAT entry with an access-list it creates a simple entry

When NAT uses a route map to decide to create a translation entry, it will always create a "fully extended" translation entry. This translation entry will contain both the inside and outside (local and global) address entries and any TCP or UDP port information

HTH, rate if it does


sqambera Tue, 07/03/2007 - 04:07
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Thanks Narayan. You understood exactly my problem and what you suggested has solved half of the issue that I am experiencing. Now what about the second NAT command which I mentioned in my orginal query? Is there a way to redirect incoming traffic on both iterfaces (fa0/0 and fa0/1) to firewall also?

Let me expalin it again:

I have following command configured on my router:

ip nat inside source static interface FastEthernet0/0

is there a way that I can configure the same command again on my router but with interface fa0/1 at the end? So there will be ultimately two of these commands configured on my router. Thanks.


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