installing as a degraded RAID-1 mirror

[Jack Howarth]

    Does anyone know if it is possible to install FC4 on a new
machine with a single SCSI drive as a degraded RAID-1 mirror?
That is, can one just create a set of software RAID-1 mirror
partitions in diskdruid using just the partitions from a single
drive? The idea would be to get FC4 on the machine and then
add a second SCSI drive later to use for the missing RAID-1
partitions. Also, I have had good luck with the performance of
two SATA drives attached to the same Promise SATA controller.
What sort of speed hit am a likely to take by using two SCSI
drives on the same controller compared to the SATA configuration?
               Jack