ubuntu 10.04 VPN connection failed

装了ubuntu 10.04,vpn老是failed，搜了好久，找到了解决方法。


http://swiss.ubuntuforums.org/showthread.php?p=8339242#

3. PPTP VPN Configuration - This setup works for connecting to ISA 2004/2006 PPTP VPNs. It should work for connecting to MS PPTP VPN implementations in general. I can't speak for other PPTP VPN implementations.


    a. Create new PPTP connection

        * VPN Tab Settings

            * Set Connection name
            * Set Gateway
            * Set username (for domain-based user accounts, use domain\username)
            * DO NOT SET PASSWORD
            * DO NOT SET NT DOMAIN

            * PPTP Advanced Options (Advanced button)

                * uncheck all auth methods EXCEPT MSCHAPv2
                * check "Use Point-to-Point encryption (MPPE)"

                                      o leave Security set at "All Available (Default)"
                                      o trying to force encryption level causes this option to become unset

                * check "Allow stateful inspection"
                * uncheck "Allow BSD Data Compression"
                * uncheck "Allow Deflate Data Compression"
                * uncheck "Use TCP Header Compression"
                * uncheck "Send PPP Echo Packets" (although connection works either checked or unchecked)

            * save configuration

    b. Initial Connection attempt

            * enter password in login box
            * DO NOT check either password save box at this time
            * once connection establishes, verify remote connectivity - ping, rdp, ssh, etc.
            * disconnect VPN session

    c. 2nd connection attempt

            * enter password in login box
            * check both password save option boxes
            * once again verify remote connectivity
            * disconnect VPN session

    d. Subsequent connection attempts

            * VPN session should automatically connect using saved auth credentials