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Community Member

PIX doesn't support transparent tunneling mode??


I'm running a PIX 6.1(4) and the customer can happily dial into the Internet via a modem an connect using the 3.6 client but when he tries from behind his NAt'd router the tunnel comes up but no ip traffic passes.

Reading the manual for the VPN client it seems to suggest that he needs to run Transparent Tunneling, but checking this option on the client doesn't seem to make a difference.

Can you confirm either

a) The PIX software version I'm running doesn't support transparent tunneling mode and if so, which vesions do?


b) Do I need to make config changes on the PIX to support transparent tunneling?

I've got happy customers using straight VPN tunnels and non-clientside-NAT VPN client access.

Many thanks,


Community Member

Re: PIX doesn't support transparent tunneling mode??

From what I understand, there are no versions of PIX code which support it. Version 6.3 is supposed to, but I don't know when it's due to come out (does anyone?).

Checking it on the client will not make any difference in this case.

Community Member

Re: PIX doesn't support transparent tunneling mode??


It sounds like yo might be what they sometimes refer to as the "double NAT dance"

We had that problem with users that have NAT'ing devices but while connecting to a 3060 Concentrator.

Try opening up the VPN Dialer, click options, click properties, click on the General Tab, Look for Transparent Tunneling and uncheck it. Then reboot the system and try it again.


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