RHEL 4.5 4.6 5.0 cant detect external DAT72 HP Storageworks SCSI tape drive

[sunhux G]

I have several RHEL 4.5, 4.6 & 5.0 boxes which I've tried
insf  mknod & cat "- - -" > /proc/sys/.../scan/...  device
file to try to detect the tape drive but no joy (as doing tar
to /dev/st0 or st1 or st2 doesn't result in the DAT72's LED
light to blink;  I've tried setting the SCSI id of the DAT72
SCSI drive to 1 & 2)

I'm moving DC.  What is the safest 'bare metal backup'
to a DAT72 tape that I can take in the event both the
Linux servers' boot disks got damaged (it ever occurred
in one past DC move I've been thru before) during the move
so that I can recover without reinstalling Redhat?

Can I use "dd" & is the syntax below Ok:
  ' dd if=/dev/sda of=/dev/st0  bs=64k conv=notrunc '

In the event both boot disks are damaged during transit,
can I just boot up from RHEL 4.x / 5.0 CD/DVD & then issue:
  'dd if=/dev/st0 of=/dev/sda  bs=64k conv=notrunc'

Or is there any way to create a bootable DDS3 tapes
(yes, I would like to read/write DDS3 media on HP
  Storageworks  DAT72 drive, would this work?)


If there's drivers that need to be installed, kindly point me
to the exact urls/links to download for this HP Storageworks
DAT72 for  RHEL 4.5/4.6/5.0


Tks
Sun