interesting article, for all those who think Ubuntu is already easy

[Alan McKinnon]

On Thursday 25 May 2006 04:19, Michael T. Richter wrote:
> On Wed, 2006-24-05 at 21:02 -0300, Derek Broughton wrote:
> > >> Thankfully, /dev/cdrom fixes that for us.
> > >
> > > Apparantly not; my DVD-burner is set to /dev/hdb.
> >
> > And you have no link from /dev/cdrom?  I don't see how you could
> > be missing it unless you've removed udev.  My dvd is /dev/scd0 -
> > but there are links from /dev/cdrom, /dev/cdrw, /dev/dvd,
> > /dev/dvdrw and possibly others I don't even know.
>
> I have a CD-RW/DVD-ROM combo and a full DVD+-RW.  /dev/cdrom, et
> al, point, essentially, at random between the two depending on
> whether or not the latter (on USB) is plugged in.

That's udev doing that. The default on most distros is to assign them 
kernel names in the order they are found. If the USB drive is found 
first, it gets the name /dev/hdc and somewhere else is there is a 
udev config that symlinks /dev/cdrom to /dev/hdc.

This is the only sane default, but it does cause the problem you 
mention. udev can be customized to your needs so that you can drill 
down as far as the serial number of the drive if you want and create 
exactly the symlinks you prefer.

udev is under heavy development and things are changing fast - it's 
now at the stage where hotplug can be dispensed with. But you still 
need to edit /etc/udev/rules.d/50-udev.rules by hand. The day will 
come soon when the OS will respond to a udev event by popping up a 
dialogue saying "This is a new drive you have never used on this 
machine before. What would you like to call it in future?" It's just 
not really for that yet.

-- 
If only me, you and dead people understand hex, 
how many people understand hex?

Alan McKinnon
alan at linuxholdings dot co dot za
+27 82, double three seven, one nine three five