Interesting recovery frustrations

[Basil Chupin]

On 18/12/2010 12:40, Tom H wrote:
> On Fri, Dec 17, 2010 at 5:25 PM, MR ZenWiz<mrzenwiz at gmail.com>  wrote:
>> On Fri, Dec 17, 2010 at 6:28 AM, Tom H<tomh0665 at gmail.com>  wrote:
>>> When reformatting?! Why not also include the possibility of swapping a
>>> disk out and ending up with a different hardware ID?!
>>>
>> How does this not fit into "physically moving the drive connectors?"
>> Don't confuse physical changes with software-induced modifications -
>> there is a significant difference.
>>
>>> I recently had a box where the kernel module load order changed after
>>> an update and the device names changed.
>>>
>> That sounds quite unusual to me, but it is indeed on a par with a
>> hardware change that affects drive order - how often does a kernel
>> module change affect drive ids?  Rarely.
>>
>>> So device names aren't more
>>> persistent than UUIDs or labels (at least for that reason). For a
>>> single install, filesystem UUIDs don't change except when you dual-,
>>> triple-, quadruple-, ...-boot and you allow mkswap to run during the
>>> install of the nth OS. The swap partition's UUID is then changed...
>> When you generalize from a corner case, you weaken your own argument.
>>
>>> You seem to be agreeing with the earlier ranter about using device
>>> names and thereby deviating from Ubuntu standards in a worse way than
>>> enabling root because you can (CAN!) make a system unbootable.
>>>
>> If you insist on reading your own ideas into what I posted, you are
>> free to do that but it doesn't make your words mine.  If you're
>> *asking* if that's what I said, the answer is no.
>>
>> What I said is that I prefer to use labels for device naming and
>> mounting. mainly because *I* decide what the labels are, not a
>> formatter or the OS or the hardware.  *I* prefer that level of
>> control.  Using labels I was able to recover and boot my Ubuntu.  If
>> I'd had to go through at least one other round of live CD booting just
>> to read the UUIDs and possibly get them wrong, I might have gone
>> completely mad.  My labels gave me a shortcut that worked.  Others are
>> free not to use that method, and if newer works for you, go for it,
>> but don't expect everyone to.
> I shouldn't have wasted any time on this thread...

I agree. You shouldn't waste anyone's time with your ramblings.

At least Karl can claim age for his behaviour but what's yours? Possibly 
going through the menopause (using the alias of Tom H on gmail could 
even mean that you are a cross-dressing Tomasina - I have no problems 
with you cross-dressing, if this is the case, nor with any other degrees 
of orientation, just to make it categorically clear)? But you always 
acting like a shrew when it comes to some posts makes one ask this 
question..... No offence intended, of course.

Let's just have a look at a few things in support of the "UUID" concept 
in practice.

When you are installing Ubuntu, what shows up on the partitioning tool 
if you want to go the "expert partitioning' way? Oh dear..... no UUIDs 
but just /sda etc <sob> :'( .

Have you looked at your mtab entries lately? Here is a small extract:

/dev/sda9 / ext4 rw,errors=remount-ro,commit=0 0 0

See the UUID entry. No? Oh dear...... :-( .

Or what do you see when you use Disk Utility under System>Administration 
(or even gparted)? See any UUID mentioned there? No? Oh dear.... :-( .

How about when you use fdisk or cfdisk or sfdisk? All full of UUID 
entries to identify the partitions, aren't they? They show no UUIDs?! Oh 
dear.... :-( .

Oh, and what about this entry in /etc/default/grub

# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to 
Linux
#GRUB_DISABLE_LINUX_UUID=true

An option to not use those "vital" UUIDs even for GRUB..... Oh dear, oh 
dear :-( .


All showing how crucial it is to use UUIDs as the device identifiers, 
aren't they?

BC

-- 
"Everybody wants to go to Heaven but nobody wants to die."