Vpnc
vpnc is a VPN client for Cisco hardware VPNs.
Installation
Configuration
The vpnc configuration files are in /etc/vpnc. It contains a default.conf file that you can copy and modify for your setup.
Executing vpnc --long-help will provide the names and descriptions of the various configuration options. For instance, in that output you will see
--gateway <ip/hostname>
IP/name of your IPSec gateway
conf-variable: IPSec gateway<ip/hostname>
which translates into a line like this in your configuration file:
IPSec gateway gateway.example.com
Starting
The vpnc package comes with a systemd unit vpnc@.service. If you want to use the configuration file /etc/vpnc/client.conf, you would start it with systemctl start vpnc@client.