YDL, Firewire, and SCSI devices

[Michael George]

On Jan 5, 2004, at 11:20 AM, Michael George wrote:
> This post is mostly as a head's up and something to go into the  
> archives for anyone who is trying to work with a bootable firewire  
> drive.  I ran into this problem with an XServe, but it can happen with  
> any expandable system.
>
> Using two HOWTO's on the topic (http://131.204.27.45/ydl-howto/ and  
> http://lists.terrasoftsolutions.com/pipermail/yellowdog-general/2003- 
> October/010501.html) I had great success in creating a firewire drive  
> that would boot on my Power Mac and my iBook.
>
> However, we hit a snag on the XServe.  The XServe has an Atto SCSI  
> card in it with 2 interfaces.  The CD drive in this XServe is not a  
> burner (if it is, we'll be surprised).
>
> The system would boot but it would complain that it couldn't find the  
> root device was the complaint.  Odd, because it was booting from that  
> drive, after all!
>
> We noticed that when it was "scanning" for SCSI devices, the firewire  
> drive wasn't reported when it was found like it was with the iBook and  
> PowerBook.  We scanned SCSI 0 and 1.  Well, that made sense, because  
> the Atto is SCSI 0 and SCSI 1.  So we added "scanning" for SCSI 2.   
> Still no-go.
>
> SCSI 3 did the trick.  So we have the initrd boot process looking for  
> 32 SCSI devices on SCSI 0-3.  That did it.  The Atto is 0 and 1 and  
> the firewire drive is 3.  We have no clue where 2 is referring.   
> Perhaps someone who knows the kernel and boot process better does.
>
> Perhaps with more checking I'd have the answer, but I'm not running  
> that firewire drive right now, so I cannot tell.  I should be working  
> with it tomorrow so I may respond to this message then with more  
> detail.

It appears that even though we don't have a CD-burner, the ide-scsi is  
there as a scsi interface.  The Atto has controllers 0 and 1, ide-scsi  
has controller 2, and that put the firewire drive at controller 3.

-Michael