How Kernel Hacking Skills make you seem less of an idiot

I'm setting up a new mail server, and wanted to get the on-board Serial ATA RAID going. Adventure inside.

This Intel Hudson server has an Intel ICH5 SATA150 controller, which has on-board ATA RAID support for RAID0/1/5/0+1. But despite fifteen minutes staring at the bootup and the BIOS, I can't see any utility to set it up in the BIOS.

Never fear, FreeBSD can do this for you, using the nifty 'atacontrol' utility.

A few places on the web suggest that you can use atacontrol's create while (single) booted off a minimal install on one of the disks. No go for me.

This is where the idiocy occurs:

# atacontrol create RAID1 ad6 ad6

Why would I do such a thing? Well, I was getting the same errors with atacontrol create RAID1 asdfadsjkas ad6 as I was getting with atacontrol create RAID1 ad4 ad6, and I was wondering whether I has a syntax error. But lo, it worked just fine.

So, a bit irritated, I reboot, deciding to make a kernel with an MFSROOT with atacontrol on it so I can run atacontrol from there.

Boom! The sound of FreeBSD's ATA RAID support trying to open ad6 twice put it in a mirror of itself. Even booting from the CD attempts to configure the RAID array...

So, I rip out ad6 and I create a quick patch to FreeBSD's ATA system not to attempt to manage the RAID on bootup, and build a new kernel, without modules, and reboot. Another boom - apparently this server requires ACPI to boot on FreeBSD. At this point, I decide to just get another IDE drive, install on there, patch the kernel on it, get both drives up, and run atacontrol while mounted on the IDE drive instead of one of the SATA drives. Success, and reboot with install CD, and install to ATA RAID array. Yay!

ar0: 152627MB  [19457/255/63] status: READY subdisks:
 disk0 READY on ad4 at ata2-master
 disk1 READY on ad6 at ata3-master

Not sure what it's behaviour is supposed to be like, but I'm happy with this performance:

            ar0
 KB/t tps  MB/s
128.00 430 53.71
128.00 446 55.69
128.00 438 54.70
128.00 434 54.21
128.00 436 54.45
128.00 443 55.32
128.00 439 54.83
128.00 439 54.83
127.43 440 54.70
128.00 439 54.83
128.00 437 54.58
128.00 439 54.83
128.00 439 54.83
128.00 438 54.70