VPN doesn't work since changing ISP's

Posted on 2007-10-10
Last Modified: 2013-12-25
We had an existing VPN working properly.  We since have changed ISPs.  I changed the Outside IP address and Route on the PIX 506e router at the main site to connect to the new ISP.  Internet service at the main site works fine.  I then change the VPN client server IP address on the client PIX 501.  Client sites also have Internet service that work fine.  The problem is the VPN tunnel does not work anymore.  Also cannot get into the PIX 506e at the main site anymore through SSH (outside).  Any Ideas what happened.

Question by:dupont2406

    Author Comment

    Also the VPN Tunnel light is on the the pix 501 client
    LVL 5

    Expert Comment

    You will want to check with the ISP to find out what ports they allow and compare to the ports you are using for your VPN.
    LVL 36

    Accepted Solution

    At the main site you will need to change the IP address and route.
    At the other site you will need to update the IP address of the peer VPN server in the 'crypto map' command and the 'isakmp key' command.

    You will also want to run the 'clear crypto sa' command (or reboot the pix) at both ends so the old vpn information is reset other it can cause problems with the new settings.
    LVL 16

    Expert Comment

    ya try a reboot as grblades has said as i have seen this causing problems before
    LVL 2

    Expert Comment

    Your new ISP may use a diferent size MTU, that might be worth a look.

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