I use quite a lot of vpns. On any given moment I have between 3 and 10 active vpn connections from the machine I'm working on.
I generally tend to use OpenVPN, but I also do use vpnc (Cisco VPN client).
One thing that I noticed is not very commonly known, and ( in my case – helps a lot ), is that you don't have to have your tunnel interfaces named tun0, tun1, tun2 and so on.
You can do something like this:
in /etc/vpnc/tunnel.conf, add such line:
Interface name <strong>depesz</strong>
and enable the tunnel – you will see that instead of boring, and somewhat cryptic “tunX" interface you'll have interface named “depesz“.
Similar thing for openvpn – in it's conf file for tunnel add these 2 lines:
dev-type tun dev <strong>smart</strong>
First line is new one (usually), and is required so that OpenVPN can know if you want TUN or TAP tunnels. “dev" is usually “tun", but it can be changed, and with above lines, will make the tunnel interface named “smart“.