Similar Experience/Forget Hardy

Rashkae ubuntu at
Wed Jun 11 18:45:32 UTC 2008

Steve Lamb wrote:
> On Wed, June 11, 2008 10:20 am, Nils Kassube wrote:
>> If you have more than one drive in your machine, it isn't guaranteed that
>> it will always get the same device name. Therefore, it is useful to use
>> UUIDs even for internal disks.
>     Still trying to figure out when that change went into effect and whom,
> exactly, thought it was a good idea.  I mean the traditional method is
> that the position in the chain determines the letter and the partition
> determines the number.  I certainly would hope that sda5 doesn't
> suddenly come up as sda2 nor that somehow the 2nd drive in the chain
> (sdb) somehow swaps with the first drive in the chain (sda) without some
> external force physically moving it.  However, if that physical force...
> ME.... moves it then I bloody well know why it is not sda instead of
> sdb.  :P

The real source of the problem is that all modern PC's have more than 1
chain, if you have device on each, it's entirely undefined which chip
(IDE vs SATA, for example) will be first to grab sda/sdb and which will
be sdc and sde.  (If you boot from an IDE CD-ROM, for example. you bios
will make the IDE primary, and kernel picks up sda, and all your SATA
drives get the later letters.  Next time you boot from SATA, and they
are reversed.. Made installation interesting.)

Added to that complexity, Ubuntu was aware that several IDE chipsets are
now supported by the libata drivers, which change their device names
from hd# to sd#, and lets not forget the wrench that hotplug hardware
adds to all this.  Oh, and the support nightmare when a less technical
person tries adding hardware and required to move some drives around in
their system... try stepping them through identifying what each drive
should be in changing fstab in a system that doesn't boot anymore.....

I could go on, but I think you get the point.. even though you
personally don't like it, surely you can see it was a damn good idea.
UUID should be transparent to the average user and makes fstab 100% robust.

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