1. Package requirement You will first need to get the vpnc package and install it. Fire up a terminal and enter this command:
      sudo apt-get install vpnc
  2. Configuration file
      cd /etc/vpnc/
      cp default.conf mmw.conf 
      IPSec gateway
      IPSec ID       <XXX>
      IPSec secret   <XXX> 
      IKE Authmode hybrid # <hybrid/psk/cert> 
      Xauth username <XXX> 
      Xauth password <XXX> 
      (Optional) NAT Traversal Mode natt # <natt/none/force-natt/cisco-udp>
  3. Usage
  • Connecting to a VPN
    e.g., sudo vpnc mmw --enable-1des --local-addr --local-port 500
    ubuntu@yc-ubuntu:/etc$ sudo vpnc mmw --enable-1des 
    VPNC started in background (pid: 22892)...
    ubuntu@yc-ubuntu:/etc$ ping
    PING ( 56(84) bytes of data.
    64 bytes from icmp_seq=1 ttl=63 time=0.915 ms
    64 bytes from icmp_seq=2 ttl=63 time=0.764 ms
    --- ping statistics ---
    2 packets transmitted, 2 received, 0% packet loss, time 1030ms
    rtt min/avg/max/mdev = 0.764/0.839/0.915/0.080 ms

    If you get error: vpnc: response was invalid [2]: (ISAKMP_N_INVALID_EXCHANGE_TYPE)(7), it is because you false settings of authentication (hybrid instead of psk) so you have to change your .conf file as above meantioned. [1]

  • Disconnecting from a VPN
    sudo vpnc-disconnect

Other platforms

More on decrypting the Group password [2] provides the source code use to decrypt the group password.



  1. Installing Cisco VPN and VPNC in Ubuntu
  2. How-To: Connect to a Cisco VPN with vpnc