[linux-lvm] About Extending LVM size with Hardware Raid

[Glen Harris]

Clint Byrum wrote:
> Side Note: if anyone knows of a cheap way to hotswap PATA disks, I'd
> like to hear about it. Right now I stick 'em in a crappy old box with
> those $2 removable IDE tray things, and have to reboot that box whenever
> I'm done copying stuff to the disks. No big deal, but it seems kinda
> cheesy. :-P

PATA disks are difficult. There is a very slight chance of damaging the
interface electronics, and motor driver electronics. There is also a
chance of data loss, as it is difficult to guarantee that no write-
behind cache is in operation. Finally, the operating system has to
be able to disable an IDE device and redetect it, including partition
tables, etc - somewhat of a grey area in the Linux kernel from my
reading of the kernel sources. If that's changed, please let me know!

There are cheap($30) hotswap caddies with a power switch which removes
power from the drive and places the interface bus in Hi-Z state, but
this still leaves the caching and operating system disable/redetect
issues.

Cheers, glen.