scsi2ide Hardware Raid5 questions

[Christian Guggenberger <christian.guggenberger@physik.uni-regensburg.de>]

Hi,

we just bought a Infortrend IFT-6300 scsi2ide hardware Raid. It consists 
of 12 Maxtor 160GB drives and is connected to DualPII via an adaptec 29160 
scsi controller.(32bit pci only).

I configured it as Raid5 with all 12 drives and so has a capacity of about 
1650 GB.
Here my Problems start:

I tried latest 2.4-xfs cvs kernel and 2.4.19-pre8aa2.

1. aic7xxx reports a negative size of that big scsi array.
Can this message be ignored? I tried fdisk and finally got a working 
partition table on this device.

2. The IFT-6300 comes with no documentation about block, stride and stripe 
sizes.
Is it safe for me to use mkfs.xfs without any sunit and swith options?

thanks in advance

Christian Guggenberger