Category Archives: Unix
Debugging the OpenBSD kernel via QEMU
Recently I had to track down a minor bug in the OpenBSD kernel. I tapped QEMU and GDB as debugging tools for the task, running on Ubuntu 12.04 as the host OS. This combination worked extremely well, so for the … Continue reading
PXE booting OpenBSD on an ALIX via Ubuntu Live CD
Update: I’ve expanded the contents of this post into a full guide to running an OpenBSD router on an ALIX board. This is a quick guide to booting the OpenBSD installer on a PC Engines ALIX board with tinyBIOS (such … Continue reading
Mobile LAN-oriented filtering in iptables
One of the things that I really like about pf, the OpenBSD firewall, is how it lets you define dynamic packet filtering rules — rules that filter based on your network interfaces’ current addresses at the time of filtering. For … Continue reading
Patch for segfault in OpenBSD 4.3′s pfctl
A couple of months ago, I upgraded an old PowerPC machine from OpenBSD 4.2 to 4.3, and I discovered that the new version of pfctl in 4.3 would segfault when reading my old pf.conf file. Some brief poking around with … Continue reading
ISC DHCPD status report generator
After setting up my apartment’s OpenBSD based network, I decided it would be handy to have a simple report generator to describe active DHCPD leases. I also wanted to brush up on Perl a bit. This Perl script is the … Continue reading