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New Member

HELP: How do i pass through public IP's from dialer interface to physical interface without NAT?





I'm having alot of trouble trying to do something reasonably straight forward, or so i thought.  I have been given a /29 ip block by my ISP, im using a Cisco 2811 router with an ADSL HWIC.  If i set the dialer interface to "ip address negotiated" it works fine, but i want to put that ip block directly on the inside interface so i don't have to use NAT overload or static 121 NAT.


I have tried putting my block of IPs on Gi0/1 and removing "ip address negotiated" from the dialer interface and replacing it with "ip unnumbered GI0/1" thinking it would force the dialer interface to take the ip from the GI0/1 instead.  However i just cant get out to the internet when i do this.


Am i missing any commands or am i doing it wrong?  I have googled this o nthe web but can't seem to find the answer which is odd, everybody uses NAT instead.


Passing through a public block from an ISP to a physical interface shouldn't be too difficult surely?



Can anyone crack this for me?



Many thanks!




Just as an extra note i found this article which is similar to what i want to do but uses a vlan interface (because its a 887 and has switchports for access)



New Member

Ok i have cracked it, i had a

Ok i have cracked it, i had a typo in the IP address on the physical interface, this now works as intended, it appears i have answered by own question.....



Cheers anyway.



New Member

Hi Matt,Could you post a

Hi Matt,

Could you post a config of yours.

I am trying to do a similar thing. I've got a block of /29 addresses, and would like to use 1 Public IP for the router and 1 Public IP for the firewall which is behind the router.

Did you have to Bridge the Dialer interface with FA? 

How did you end up solving this mystery?

I also do want to avoid 121 NATing.



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