[linux-lvm] LVM on an external USB device - why not?

[Ian Burnett]

My current system configuration is a 250GB internal IDE HDD, managed 
using LVM2 under Fedora Core 6. What I would like to do is to put this 
disk into an external USB enclosure to reduce heat generation inside the 
PC. Another reason is to allow the addition of extra disks very easily 
(current case only has room for 1x 3.5" HDD).

Once the USB drive is connected, I will be performing the initial boot 
stages off a small (2GB) solid-state CF disk, so I don't necessarily 
need the full "boot from USB" capabilities.

I can't see any problems in doing so myself. I realise that if 
additional usb-storage devices are added, then the raw device may change 
from /dev/sda to /dev/sdb, but with LVM using PV UUIDs to locate 
devices, won't that be irrelevant?

Are there any caveats to doing this? I haven't seen anything 
particularly relevant on the archives of this mailing list, and I've 
Googled around the subject. I did discover a couple of boot-from-USB 
walkthroughs scattered around the web which unhelpfully said "don't do 
it" without giving any particular reasons. That was from some old posts 
(c. 2005), without any citations, and didn't mention LVM2 so could have 
been based on LVM1.

All advice welcomed.

Ian.

-- 
Ian Burnett :: www.ianburnett.com