setup-storage with 3ware controller and additional drives

[Carsten Aulbert]

Hi

again, I'm struggling to get a problem with setup-storage solved. One of our 
machines has 8 hard drives, 4 of them are connected to a 3ware controller and 
set to export two logical devices. Additionally, there are 4 identical hard 
drives attached, i.e. I expect sda..sdf which I get.

The problem is, how do i get the setup-storage configuration file set-up 
correctly and generic enough to work also a second time in a couple of month, 
if one of the disks has been replaced?

The problem is: 

* I cannot use sda...sdf as these may change upon reboot - checked and this 
happens

* in by-id I have scsi-SATA_Hitachi_HUA7210_GTE200P8G3JYGE for the 4 drives 
(well except the final characters as these are based on its serial number), 
while the 3ware controller is scsi-3600050e0f0998500d158000028c10000 and 
scsi-3600050e0f0998500d1580001e8960000

* by-uuid is not of much help

* by-path is interesting, but is this

lrwxrwxrwx 1 root root  9 Jan  9 13:17 pci-0000:00:1f.2-scsi-0:0:0:0 -> 
../../sda
lrwxrwxrwx 1 root root  9 Jan  9 13:17 pci-0000:00:1f.2-scsi-1:0:0:0 -> 
../../sdd
lrwxrwxrwx 1 root root  9 Jan  9 13:17 pci-0000:00:1f.2-scsi-2:0:0:0 -> 
../../sde
lrwxrwxrwx 1 root root  9 Jan  9 13:17 pci-0000:00:1f.2-scsi-3:0:0:0 -> 
../../sdf
lrwxrwxrwx 1 root root  9 Jan  9 13:17 pci-0000:03:00.0-scsi-0:0:0:0 -> 
../../sdb
lrwxrwxrwx 1 root root  9 Jan  9 13:17 pci-0000:03:00.0-scsi-0:0:0:1 -> 
../../sdc
lrwxrwxrwx 1 root root  9 Jan  9 13:17 pci-0000:05:00.0-scsi-0:0:1:0 -> 
../../sr0


really stable across reboots?
and then how does one differentiate between 
pci-0000:03:00.0-scsi-0:0:0:0 and 
pci-0000:00:1f.2-scsi-0:0:0:0

(3ware first device and first stand-alone disk)?

Anyone knows how to tackle this?

In the end I want to have the system on 3ware device one, then once FS on 
3ware device 2 and finally a software raid across the 4 disks.

Cheers

Carsten