iptables

Firewall configuration programs (fwbuilder, yast2, iptables, Brickwall/Brickhouse)

Configuring the firewall by hand using iptables is quite difficult. When we still used RedHat 8.1 we have been doing it but now not anymore. We have been using yast2 now for firewall configuration. An alternative to yast2 is fwbuilder. We tried it once and it seems to work although the code it produces is quite large compared to manual configuration. An obvious advantage is that fwbuilder can be used together with many different types of firewalls and operating systems (e.g. also Mac OS X).

How to enable VPN clients to access LAN computers that are not running VPN software

I installed an OpenVPN service on our server. The default setup worked right out of the box. However, I wanted to use a VPN client to perform offsite backups of the computers in our LAN (using the backuppc software). First I installed OpenVPN clients on all of the LAN computers to be backed up, but OpenVPN on MacOS X seems to be a bit unreliable. Therefore I wanted to setup the VPN server to forward requests to our LAN network. The following changes were necessary: