Expanding Raid 5 Drive Array

[Ayman Altounji]

We have a proliant 6000 server with a SMART-2DH Array Controller
with one channel configured as RAID 5 with 4 hot swappable drives of 4.3, resulting in 12 GB usable harddisk partition under windows NT 4.
Now we want to expand this to min 30 GB usable size.
We are thinking of replacing the four drives of 4.3GB with 3 drives of 18 GB to create a usable space of 36 GB.
Is this possibly ? If so, is this possible by just replacing the drives on the fly or must the data be backed up first and then restored on the new drivers.

Which drives of 18 GB must be ordered, can we use the following:

18.2 GB Pluggable Wide-Ultra SCSI-3 7200 rpm Hard Drive
????(400739-B21)

Note: The manual of the Smart-2DH Array Controller doesn't mention that harddisks greater than 9.1 GB are supported, should I Upgrade the firmware ?

[Ayman Altounji]

You'll need to upgrade the firmware on the Smart 2DH and you'll need to replace all four drives in the Array instead of 3 . The 18gb drives you selected can be used .

[Ayman Altounji]

What is the best way to go about this? Do you just fail one 4.3Gb drive at a time and put an 18Gb drive in it's place? Then once you have done that to all four drives you can expand the volumes?