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Vpn from private IP

Pelitti asked
Medium Priority
Last Modified: 2013-11-16
my configuration is:
Office: pix 506E, 6.3(5) Outside ip: static - public

ADSL Router Outside ip: Dynamic - public
PIX 501 6.3(5) Outside:, Gateway:
Inside: , clients: 10.12.7.X

When i am at home, from My laptop, with Cisco clients v 4.8 i am able to connect by vpn to office.
I am trying to configure the hpme PIX to connect office PIX by vpn, so all my home pc are tunnelled.
I configure all but the log say:

ISAKMP Phase 1 retransmission (local (initiator), remote xxremoteIPxx)

702303: sa_request, (key eng. msg.) src=, dest= xxremoteIPxx, src_proxy= (type=4),
dest_proxy= (type=4), protocol= ESP, transform= esp-des esp-md5-hmac ,
lifedur= 28800s and 4608000kb, spi= 0x0(0), conn_id= 0, keysize= 0, flags= 0x4004 is the internal private network on office pix.

It is possible configure the home pix to do this, or is impossible without a pubblic ip address on outside interface ??

Thank you,

Watch Question

It most certainly is possible to do this with your home PIX connected to the ADSL router. I have many remote offices that are connected in this way. The small ones of 2-3 temp staff can only justify ADSL broadband.

The PIX has an outside IP, which is linked to the inside ADSL network, but you need to make sure the ADSL router/modem is configured to be in passthrough mode. This will then 'publish' your outside IP address through and onto your other PIX in your office.

You need to make sure your PIX does all the firewall work (as it should) as well as DHCP/routing if required for your home network of PC's.

Hope this helps

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Passthrough mode. ok i will check. I have only 1 pubblic ip on he router, the outside of my pix is private, so when the vpn start, the caller ip must be natted, it is correct ?

Thank you,
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