OpenBSD and WRAP Board

As a router, I had a modified Linksys WRT54GL running DD-WRT as a wireless router, and I also run an OpenVPN session on that. As you understand that router couldn’t handle that much.

I had a WRAP board doing nothing, so I thought it would be nice if I used that, since it has a 233MHz x86-class CPU and 128MB RAM. Enough to handle a lot.

I tried several firewall distributions for that platform, but I couldn’t get them to do what I wanted, so the solution was to install a vanilla distribution of an OS and customize it as I wanted.

The operating system of choice in such cases is usually OpenBSD. The only problem was how to get it installed on such a board, since no CD Drive or monitor was available. The only way to do it was using net boot and serial console.

By default, OpenBSD does not start the serial console for installation, but thankfully this guy has some images with the Serial Console enabled. The next problem was how to net boot. The WRAP board supports PXE, but then again you will need to configure your DHCP and setup a TFTP server in order to do this, adding more complications.

So, I tried writing the floppy installation image directly to my microdrive and booting the drive. Since OpenBSD was creating a ram drive to store the installation, it should be no problem to overwrite the drive with the installation.

The WRAP board booted happily from the microdrive and the installation of OpenBSD 4.1 was completed without any problems on the board. All of the hardware was completely supported, and the device was ready to route traffic within minutes thanks to the powerful pf. The board also serves as a DHCP and DNS server. I will post a follow-up post regarding the services.

Overall, this is a nice setup for a firewall. With OpenBSD 4.2 and the promised upgrades, you may archive up to 50Mbit/sec throughput on such a board, which you need several thousand pounds to do that with a commercial firewall.