bios disk numbers and device names

[Michael Grant]

On Mon, Nov 29, 2004 at 09:33:25PM +1030, Daniel O'Connor wrote:
> On Mon, 29 Nov 2004 20:40, Michael Grant wrote:
> > Is there any way to statically assign a device name to a specific disk
> > so that if the BIOS renumbers the disks (for example if I move around
> > a controller) so that the devices always come up with the same name?
> 
> The BIOS naming means nothing to freebsd (in general).
> 
> I don't think there's much you can do - device names are based on the order of 
> probing so if you change which slot on the controller it's connected to it 
> will change device name.
> 
> What sort of device in particular?

Specifically, ata and scsi.  This is a big problem for me.  Once I
lost a controller and it was a nightmare trying to get the machine to
boot after moving the disks to the other controller.  Another time I
added a disk and again it was a nightmare.

Has anyone thought about this problem?  Is there some spare space in
the label that could be used for a device name that, if set, could
be used in place of (or an alias for) a name like da0?

Michael Grant