Re: [RFC] aic94xx: attaching to the sas transport class

[Mike Anderson <andmike@us.ibm.com>]

James Bottomley <James.Bottomley@SteelEye.com> wrote:
> On Fri, 2006-03-03 at 16:58 +0100, Stefan Richter wrote:
> > James Bottomley wrote:
> > > Assuming the cages are all powered up, which is beyond
> > > the driver control, then serialising the scan will allow one to
> > > specify /dev/sda1 deterministically for root.
> > 
> > Does SAS provide a persistent globally unique property of a device, or
> > has SAS to rely on bus topology to uniqely identify devices?
> 
> Yes ... naturally; all modern SCSI devices provide a variety of ways of
> identifying them. In the fullness of time, I expect udev and initramfs
> to support all of these, allowing the user free range of specifications.
> I also expect the boot system to provide a timeout (or wait forever)
> parameter for delaying before these become visible.  However, none of
> these problems are kernel issues.

Well this may not be kernel issue, the perception to many users is that
something is wrong with the IO subsystem.  I would agree we know how to
solve this, but I have need seen any distro based mkinitrd scripts
generate an initrd with a "wait for root dev" step. 

Does anyone know of a distro initrd / initramfs creation script that has
this support? As a side note I do not understand historically why one
would every want to leave the initrd without a root dev present and end in
an oops.

-andmike
--
Michael Anderson
andmike@us.ibm.com