OpenConnect is a client for Cisco’s AnyConnect VPN. It is free software, and is released under the GNU LGPL v2.1 . Getting connected to an AnyConnect VPN is easy with OpenConnect and the TUN/TAP kernel module that is built into the Linux kernel.

1. First run command below to active th TUN module:

sudo /sbin/modprobe tun

2. Install OpenConnect:

sudo apt-get install openconnect

3. Connect to VPN, run:

sudo openconnect yourvpn.example.com

It prompts you to type in username and password. Once these are authenticated, the VPN connection is established.

Keep the terminal window open while the VPN session is active. Network resources such as shared folders, NAS drives, servers, and workstations should now be available. To close the VPN session, press Ctrl+Z in the terminal window. Abruptly killing the terminal window without properly closing out of the VPN session can lead to issues when attempting to reconnect in the future. These issues can typically be resolved by restarting the machine.