good in the aftermath of bad

Popular political scientist Thomas Homer-Dixon was on CBC Radio One’s The Current this morning discussing his new book, The Upside of Down. His work warns of the potential downfall of Western civilization along the lines of the demise of the Roman Empire. Although this might seem like a very gloomy topic, he makes the key point that out of catastrophe can often come good, and describes, for example, 9/11 as a squandered opportunity to, for example, reduce America’s dependence on foreign oil. But I’m getting sidetracked — and this is a journal about technology, after all, not politics. Continue reading

replacing a failed Sun LVM mirror

The problem with mirroring your disks is that one side of the mirror will invariably fail two weeks later. This has happened to me several times, first under NetBSD (with its excellent RAIDFrame technology, a worthy competitor, functionally, to Sun Volume Manager) and now with the Sun LVM mirror that I set up several weeks ago and documented in this very blog.

I called Sun support, and they shipped me a new disk. Here’s how I went about replacing the failed device, without incurring any downtime (yay, Sun hot-swappable parts)! Continue reading