Re: [Sheflug] Changing distro woes

[Alex Hudson <home@xxxxxxxxxxxxxx>]

On Thu, 2007-05-03 at 10:25 +0100, Peter Humphrey wrote:
> On Wednesday 02 May 2007 22:42:17 Alex Hudson wrote:
> > Actually, that's modern Linux I'm afraid. NIC allocations, HD device
> > allocations, etc. are all variable - the name itself isn't static.
> 
> Does udev come into this as well? It does rather seem that we're 
> progressively losing control of our own systems.

No, not really, it's actually more to do with modern hardware.

Much more stuff now is both effectively as well as technically
plug-and-play: USB devices, SATA drives, all sorts.

I can give you a great example: when I plug my laptop into the docking
station and boot from it, it has many more devices and buses attached
than when it's standalone.

If you base device naming on the order in which you come across devices,
which is the only method that really works, if anything means that order
changes (docking station in the example above, but could simply be the
hardware doesn't always go from "power on" to "ready" in the exact same
amount of time) then the name ends up changing. 

So, you have to live with the fact that device names aren't stable. For
example, in my fstab I have:

	LABEL=/         /                 ext3    defaults        1 1

If I had /dev/hda1 instead of LABEL=/, my laptop wouldn't boot every
time I dock it, because my internal hard drive becomes /dev/hde in that
scenario :)

The easy, obvious solution (that devices get static names which never
change) actually turns out to be mostly unworkable, sadly.

Cheers,

Alex.



_______________________________________________
        Sheffield Linux User's Group
  http://www.sheflug.org.uk/mailfaq.html
 GNU - The choice of a complete generation