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PIX 6.2 VPN termination - outside IP address

I'm looking for some suggestions around this problem.

PIX 535 using a registered IP address on the outside interface, this IP is used purely as a VPN termination end point. For historical reasons we're using a subnet not supplied by our current ISP, because it's only a 24 bit address some ISP's will drop this from their routing tables. We have around 100 local sites terminating sucessfully to the 535, a new office has just come on-line that's in a different country and they're unable to communicate with the external IP address - apparently due to this ISP routing issue.

So here's the crunch - I can't change the outside IP as this would involve too much work. I can't get our ISP to NAT as this could cause the locl offices to loose connectivty. I can't upgrade to 6.3 and use VLAN's as this doesn't have the relevant security accolades yet (managers eh!!). This best way around this would be a secondary IP address on the outside interface but I know this isn't possible.

So can any of you suggest anything?



Re: PIX 6.2 VPN termination - outside IP address

please excuse me for being silly, but i don't quite understand the problem.

when you configure the remote end, you dont' have to put subnet mask for the peer. so as long as the ip on pix535 is public, i am not sure why it doesn't work.

New Member

Re: PIX 6.2 VPN termination - outside IP address

Quite simply the 193.35.234.x subnet (PIX outside) does not exist in all ISP routing tables where as 195.188.208.x (our WWW servers) does! Effectively I want to put a secondary IP address on the PIX outside interface in the 195.188.208 range.


Re: PIX 6.2 VPN termination - outside IP address

Assuming your wan is a private network that managed by your isp. you may have a public ip natted on the edge of the isp network. in that case your existing vpn won't be affected. i'm sure this can be done as we had exactly the same issue before. ohterwise i guess you have to purchase another internet line, as there probably is a spare interface on 535.

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