Linux is not about choice [was Re: Fedora too cutting edge?]

[Les Mikesell]

Arthur Pemberton wrote:

>>>> Either we look at the USB device it's hanging off (vendor, product or
>>>> class id's), the driver or we provide a simple interface in
>>>> gnome-device-manager or similar (including command line apps) to set it.
>>> You're wierd dude, this essentially the same thing I suggested and you
>>> discouraged.
>> The system can't possibly work with multiple choices unless you have an
>> interface to let a human configure which is which.  Now the kicker is
>> that most of my machines are in remote locations with swappable drives
>> and I expect to be able to ship a pre-configured drive built locally and
>> have someone pop it in a known controller position and have it come up
>> working - and to be able to copy images that will work across a number
>> of identical machines without individual attention other than setting
>> the hostname and IP addresses.
> 
> 
> I would have thought that with dirves you can jsut mount by labels,
> does this not work for your use case?

First, disks aren't born with labels.  Second, most of my disks get 
created by dd'ing an existing raw disk or the equivalent, generally on a 
different machine and not necessarily under an exactly matching kernel 
that would know the filesystem or how to label it.  Third, you can't use 
labels for fdisk/mkfs, or even dump and I'd really like to know which 
physical drive is going to be the target of those commands.  I realize 
it is not an easy question.  For example the adaptec SAS raid controller 
in an ibm 3550 maps drives to volumes internally and remembers them even 
if you only have one drive in a volume.   That is, if you build a master 
image in the first slot, dd it to the drive in the 2nd slot, take that 
2nd disk and put in the first slot of another and attempt to copy again, 
your disk with contents will be detected as /dev/sdb (remembered) 
instead of sda from being in the first position.  This is fun when you 
try to repeat the dd command expecting the same thing to happen.

Anyway, the long-winded point is that you do more things with disks than 
mount the file systems they contain, so a label doesn't solve the 
identification problem.

-- 
    Les Mikesell
     lesmikesell at gmail.com