Connecting 2 sites with same subnet

BRUNO WOLLMANN · ‎09-20-2001

Hi All,

I have two sites connected to the internet and I want to establish a VPN tunnel between these 2 sites. The main site will contain a PIX515 while the other site will contain a PIX506. Both sites use 10.x.x.x/255.0.0.0 addressing schemes however there are no duplicates across the 2 sites. My question is: is it possible to establish this connection without having to re-address one of these sites? My gut tells me that this is not possible (unless I use NAT) because traffic from 10.x.x.x hosts looking for another 10.x.x.x host would never be routed outside the source site.

thanks

Bruno

srg · ‎09-20-2001

I think you are correct. The only way to get the traffic across the vpn would be to change the subnet mask at both sites.

stevent · ‎09-21-2001

My friend i saw a cisco example explaining how to do this. I have never done it but i read the article. Now i cant remember where it is but i know i saw it.

Search cisco's website its there.

Hope you find it

c.peter · ‎09-28-2001

Proxy ARP should work, as it masquerades any remote host as being on the same wire. Please consult http://www.cisco.com/warp/customer/105/5.html and related docs.

Good luck!

JOSH GANT · ‎10-30-2001

I'm not sure Proxy ARP would work in this situation. The PIX doesn't support Proxy ARP anyway. You can do this, I also saw a document on it, but it would be an ugly NAT fiasco...