Quoting Craig Sanders (cas(a)taz.net.au):
i've had it happen on kernel upgrades, and even on
reboots - a new
version of udev or something loaded modules in a different order, so
drives got detected in a different order.
I can envision that happening if your kernel suddenly changed from old
drivers/ide SATA drivers to modern libata one - a one-time changeover
that occurred sometime early in the 2.6 kernel series, if I remember
what I wrote on
http://linuxmafia.com/faq/Hardware/sata.html correctly.
I envision that happening if you use multiple, different drive
technologies (e.g., PATA and SCSI).
I have having a difficult time envisioning it happening otherwise. Your
master drive on the first PATA chain will always get the first PATA
device assignment, your third SCSI device on a SCSI chain will always
get the third SCSI device name allocated to that chain, and so on.
In short, I suspect that the applicable scenarios are either very rare
or involve hardware practices about which the best overall comment is
Don't Do That, Then.
i also dislike UUIDs because of their ugliness and
non-
human-readability so my /etc/fstab has a mixture of LABEL and /dev/md*
devices - but i understand how the boot process works well enough to
have no difficulty just editing /etc/fstab and whatever else is needed to
get my system to boot again if there's ever a problem. i expect you're
the same.
This is a good and valid point.
for people without that skill, though, it's better
that they just follow
the recommended defaults so that they don't cause major problems for
themselves.
While recognising that there's a serious cost in lack of simplicity to
adopting a method that makes your hardware more difficult to understand
and manage, in the name of protecting you from things that are wildly
unlikely if you follow elementary good practices in hardware and system
management matters.
Me, I'd say just keep a live CD around in case of a need to do system
maintenance (I like aptosid), know your system, and be prepared to
update /etc/fstab in the unlikely event of device names changing - which
is highly unlikely to occur except for perfectly obvious reasons that
you yourself triggered, e.g., inserting or removing a drive from the
middle of a drive chain, or something like that.
Or, have it both ways: Keep the UUID rubbish, but move it down to
comment lines at the bottom of /etc/fstab, the way I do, and use
/dev/sdXX for the functional lines. If you ever have problems, boot
that live CD - and you can always swap in the commented-out lines if you
can't figure things out otherwise (which I'll bet anyone here can).