[CentOS] Booting from a USB hard drive?

[Robert Heller]

At Sat, 12 Jun 2010 18:48:08 -0500 CentOS mailing list <centos at centos.org> wrote:

> 
> I'm trying to learn Asterisk (specifically Trixbox) and, as you
> probably know, it runs on CentOS. I want to run it on my laptop and
> thought that I could install it to an external USB hard drive, like
> I've done with Fedora 12 and Linux Mint 8 (I like to keep my small
> CentOS/Windows dual booting hard drive in the laptop's hard drive
> slot). But it won't work. It kept giving me hard drive errors when I
> tried to install it to the USB drive, so I installed it in the regular
> hard drive slot in the laptop -- where it works fine. But when I move
> it to the USB enclosure, it starts to boot, but can't mount the
> partitions and goes into kernel panic. I checked this with my CentOS
> hard drive and it does the same. I'm guessing the only reason Linux
> Mint works is because it refers to all partitions as "sda" instead of
> "hda" -- so it doesn't know it's in the wrong slot (just a guess).
> 
> Is there an easy fix for this? Is there some configuration file that I
> can change entries from "hda" to "sda" so the partitions will mount or
> is it more involved than that?

/etc/fstab

Also, you need to change the grub config (root=/dev/hda<mumble>).

Even better than changing from /dev/hda to /dev/sda, would be to use
labeled file systems (using LABEL=mumble instead of /dev/hdaN or
/dev/sdaN).  See 'man e2label' for more information.

> 
> Thanks for any pointers.
> 

-- 
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