How to avoid Internet Disconnection while connected to VPN on Ubuntu or any other OS

I wished to have that feature since a very long time ago and at last I found a solution which was very simple! The solution idea is simple: Don't use your base OS to connect to the VPN, use a virtual machine instead, for example I use Virtualbox as my virtualization software and I have Ubuntu 9.04 as my base OS and Ubuntu 9.10 as my guest OS, I installed the Cisco-compatible vpnc and network-manager-vpnc packages, and then connected to the VPN on the guest OS and everything worked like a charm! On my base OS I can do everything I want as if I'm not connected to any VPN and my guest OS connects to the VPN and has access to all network resources there, simple, isn't it :) ?

Update: I did the same with a Windows XP guest and Cisco VPN client and it worked fine as expected.

Install Network Manager 0.7 in Ubuntu Hardy, Intrepid, Jaunty, Karmic ...etc

A very nice site called Ubuntu PPA (Personal Package Archives) where many teams contribute their own deb packages to be used by anyone, it's not an official repository and many of the PPAs are for testing purposes only, but anyway some of them are extremely useful and can keep your software packages up to date. One of the best PPAs is the one for Network Manager (https://launchpad.net/~network-manager/+archive/ppa). To add the repository to your Software Sources list:

1. Go to System->Administration->Software Sources
2. Go to the "Third-Party" Software Tab
3. Click Add
4. Copy and paste the following line there (change jaunty with hardy or Intrepid, depends on the version you're using:
   

   deb http://ppa.launchpad.net/network-manager/ppa/ubuntu jaunty main

5. copy the following (you can get it from this url: http://keyserver.ubuntu.com:11371/pks/lookup?op=get&search=0x248DD1EEBC8EBFE8) and paste it in an empty file and save it:
   

   -----BEGIN PGP PUBLIC KEY BLOCK-----
   Version: SKS 1.0.10
   
   mI0ESXX0pgEEAMDSk9Vd+OWZNIa4dL2SpqFAjVq/hm4Nac2oc33g+BwP3jFajUC/quPnYXXl
   N7GER+tTHJ9d0PlXQDoRxXFRdSjZYUHDkiT8UV1I+sTxkjDaA7uMXD4dEcL0SG0nh6OyHHrd
   9PrWzIZ/jS6PsYtKrKwHYCvP/igPr5/bH1PQoyZzABEBAAG0IUxhdW5jaHBhZCBQUEEgZm9y
   IE5ldHdvcmstbWFuYWdlcoi2BBMBAgAgBQJJdfSmAhsDBgsJCAcDAgQVAggDBBYCAwECHgEC
   F4AACgkQJI3R7ryOv+h8JQP+Ib07jYEiNG3PZf22xkV2rU/ybI9s4fT1CCoPJq5V3uJmouUs
   jtSXMD/9V44kFamw+Xq1EVEWeExfeABjaX7Vc9SR50Kl/DJVvBAbGs8rM2JxldQsl4sGWnTn
   AMJx/fv4iQsdyaklS3TcK6xo1yL21C4j0wYsmNxS16F28L3hRQ4=
   =8t/V
   -----END PGP PUBLIC KEY BLOCK-----

6. Go to the "Authentication" tab and click "Import Key File" and then select the file you've just created above
   
7. click close
8. open a terminal and type "sudo apt-get update && sudo apt-get upgrade"
9. Now you have Network Manager 0.7.1 :), I think you might need to restart networking or restart the whole machine, don't remember exactly
10. Enjoy :)
    

Network Manager 0.7 Multiple Simultaneous Connections!

Four network connections active at the same time:

• 3G connection (etisalat USB modem)
• 2 wireless networks with 2 different wireless cards (the internal card and another external one)
• 1 wired connection

This is EXTREMELY useful and I gained a lot of benefits getting connected to multiple networks at the same time and being able to direct the network traffic to its destination using proxies, check the screenshots below:


Note that there must be one default connection (that can be changed manually since version 0.7.1) that all the traffic go to except if else specified.