OpenBSD, which bills itself as one of the most secure operating systems on the planet, just launched OpenBSD 3.5 in May, its first release to support 64-bit Opteron chips from Advanced Micro Devices. With OpenBSD 3.6, support for SMP servers has been added for both x86 and AMD platforms.

The support for 64-bit Opteron iron with the May OpenBSD release was a milestone of sorts, in that it gave a seal of approval from a widely respected group of hard-core Unix lovers for the Opteron platform. While Sun Microsystems Inc.be trying to eat up all of the press about its plans to fully support 64-bit operations on Opteron machines with the forthcoming Solaris 10 release, the team of 15 OpenBSD coders, led by Theo de Raadt, beat Sun to market with a Unix platform for 64-bit Opterons by five to six months, depending on whether Sun starts shipping in late September or late October.

Neither IBM Corp nor Hewlett-Packard Co has officially ported their respective AIX and HP-UX Unix variants to Opteron chips, but both have ported to Intel’s 64-bit Itanium architecture (which is radically different from the Xeon-64 or Opteron platforms); IBM killed off its Project Monterey Unix for Itanium, earning the wrath of partner SCO Group, while HP has over the last two years brought HP-UX functionality on Itanium on par with AIX for its PA-RISC architecture.

IBM’s and HP’s Itanium work could allow them to port their Unixes to Opterons, but there seems to be little demand for this. While it seems unlikely that IBM would ever endorse a BSD variant – whether it is OpenBSD, NetBSD, or FreeBSD – OpenBSD itself runs on Apple PowerPC machines, which means it could be ported to the pSeries and p5 servers.

OpenBSD also runs on HP’s PA-RISC servers and workstations. OpenBSD, being a close cousin to the BSD-derived Solaris, can also run on Sun 32-bit Sparc and 64-bit UltraSparc workstations and servers, as well as on Alpha and VAX machines and other vintage gear. (The 64-bit PA-RISC port of OpenBSD is on the wane, just like the PA-RISC architecture itself is.)

Incidentally, the 64-bit AMD version of OpenBSD (known as amd64) is what you load on the new Nocona Xeon DP servers if you wanted to run in 64-bit mode on those machines; if you wanted to run in 32-bit mode on either x86 or Opteron machines, you would choose the i386 version of OpenBSD.

The SMP support coming for both i386 and amd64 ports is significant to Unix nerds who want to run OpenBSD on bigger iron. The project to add SMP support to OpenBSD began in February 2000, and is derived from the work that the NetBSD project had already done to give SMP capabilities to that BSD variant (FreeBSD already has SMP support, too).

In June 2004, a secondary kernel for SMP machines was merged into the main development branch, with i386 and amd64 platforms getting first crack at the new SMP-capable kernel. That kernel went beta on the x86 and Opteron platforms in early August, and the OpenBSD project announced that it would have SMP support ready with release 3.6 on November 1. The OpenBSD project hopes to add SMP support for Apple PowerPC and Sun Sparc and UltraSparc platforms in the future, but the exact timetable is unclear.

What is also unclear is the extent of the SMP scalability of the boxes. In June, at the OpenBSD Hackathon, project members were showing off the compile times for code running on a four-way Opteron server donated by AMD. Since two- and four-way servers are the dominant x86 boxes shipped today (whether they use Xeon or Opteron chips), the OpenBSD project does not really need to go much beyond four-way SMP to make OpenBSD a lot more useful.

The fact is, OpenBSD is well known for being one of the most secure Unixes on the market, and now that it can run on bigger iron, its appeal will be broader for security-conscious companies that think OpenBSD is more secure than many alternatives, including commercial Unixes, like Solaris, AIX, and HP-UX.

OpenBSD 3.6 will have other features, including a new DHCP client and server, support for USB 2.0 peripherals, Adaptec Ultra320 SCSI adapters, and a new wireless device driver. NSF has also been tweaked to perform better and to be more reliable.

The 3.6 release will include OpenSSH 3.9 for system administrators, as well as the normal slew of open source Unix tools that have been made famous by Linux, including XFree86 4.4.0, Gcc 2.95.3, Perl 5.85, Apache 1.3.29 and Apache 2.8.16, Sendmail 8.13.0, and OpenSSL 0.9.7d. The OpenBSD project is taking orders now for OpenBSD 3.6, which costs $45 for a three-CD set. That’s a 12.5% price hike over OpenBSD 3.5, but SMP support is easily worth five bucks, right? (The commercial Unix server makers charge orders of magnitude more, rest assured.)