First off, I'm a VPN noob. We have a web server (via MediaTemple) that is running Plesk. Our client gave us .pcf files to connect to their VPN, which work locally with my mac Cisco VPN client. Plesk has a VPN module and OpenVPN is installed on our webserver. To anyone's knowledge, can I use either of these in conjunction with the .pcf file they sent us? Or do I need to install the Linux version of Cisco's software on the webserver? Thanks!
vpnc works well for this. I have used this script in the past to convert pcf files to a configuration that works for vpnc.
I wrote a blog post on how to do this if you want some hand holding with the script, this is a bit old though ...
Fedora 10+ has a Cisco-compatible VPN client included. It appears to be 'vpnc', which is available here: http://www.unix-ag.uni-kl.de/~massar/vpnc/
On Fedora 10+, NetworkManager has a GUI frontend for vpnc, but I'm sure the documentation can show you how to configure it without a GUI (if necessary).
I've used vpnc on Fedora 10 and 11 with no issues. It's easy to deal with and I've never had problems connecting.