Option to use /dev values instead of UUID values

[Liam Proven]

On Mon, Mar 15, 2010 at 6:34 PM, Florian Diesch <diesch at spamfence.net> wrote:
> Liam Proven <lproven at gmail.com> writes:
>
>> On Mon, Mar 15, 2010 at 5:23 PM, Dotan Cohen <dotancohen at gmail.com> wrote:
>>>> It would be helpful if you gave your reasons for wanting this feature.
>>>>
>>>
>>> I often have several bootable partitions, and if I have to edit fstab
>>> by hand it is easier if the /dev values are used.
>
> I'd prefer labels in this case.

If you have them. I'd agree, but the problem is, labels are optional, no?

>> Well, yes, /dev/?d? entries *are* much easier to read than UUIDs.
>> However, device names have several disadvantages, which are important.
>> A UUID is a permanent, direct link to a particular partition.
>
> No, the important difference is that a UUID is an identifier for a *file
> system* while a device name is an identifier for a *partition*.

I had to think about this, but yes, you're right. I apologise for my
poor wording.

>> If you
>> delete an earlier partition on the disk, or merge 2 of them or
>> something like that, then /dev entries change. If you delete /dev/hda2
>> then /dev/hda4 can become /dev/hda3 and so on, which can result in a
>> non-bootable system.
>
> Once my former /home became /tmp after adding a new CD drive, and /tmp
> was cleaned at boot time. I was wondering why booting took so long...

:¬o How horrible!

>> UIIDs do not change & aren't affected by this.
>>
>> If you move a partition from one drive to another, the UUID goes with
>> it - so move /home from /dev/sda to /dev/sdb and the fstab will still
>> find it.
>
> This only works if you really copy the file system (e.g. by using dd),
> but not if you create a new file system (using mkfs) and copy the files.

Well, true, but that applies to /dev nodes too. If you
copy-then-delete the filesystem into a new partition,

> AFAIR parted changes the UUID when moving or resizing partitions, too.

Really?! Not in my fairly limited experience, but that is *Not Good* if so!

-- 
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