The controller is the AAA-UDMA, a four-channel UDMA/66 RAID controller supporting up to four hard drives in RAID 0, RAID 1, RAID 0/1, and RAID 5 configurations.
The manageability and reliability
features incorporated into the AAA-UDMA are quite impressive. Adaptec's CI/O
Management software, which can be used with Windows 9x, NT4, and 2000, as well
as NetWare and UnixWare servers, is responsible for basically all interaction
with the RAID controller itself. As you might have guessed already from the
variety of operating systems supported, the software can manage any Adaptec
controllers on any system in the network- including not only the AAA-UDMA, but
also all Adaptec SCSI RAID and even standard SCSI controllers.
A password is required to make any significant changes to an array, so you needn't worry about anyone erasing your array remotely through the software. Note, however, that someone with direct access to your system can still use Computer Management under Windows 2000 or Disk Administrator under Windows NT4 to delete the volume if he has administrator privileges, so don't think that the password offers total protection from local tampering. However, it's impossible to accidentally delete a partitioned array within the CI/O software itself, as the delete option isn't available unless the operating system isn't using the array. The interface itself is straightforward, and it only takes a few minutes of looking around it to figure out how to get things done.
Creating arrays is
not difficult at all. You simply go to the configuration screen, then either go
to the Operations menu or right-click and choose Create Array. A window with all
available drives appears, and you select which drives you want to be members of
the new array. Specific drive information is displayed here, including the
drive's model number. Note that even if the drives are UDMA/100 (as my test
drives were), it shows them as only "U66". One of the panes in the window shows
which RAID levels are available given the number of drives you have selected for
the array. Hit Next, and the next window lets you name the array and choose
which RAID level you want to use.
It has an attributes section for each RAID level,
showing each type's (theoretical) relative data protection level, read
performance, write performance, and capacity utilization, as well as the number
of drives allowed for that array type (e.g. 1-16 for RAID 0, 2 for RAID 1,
etc.). Remember, this software is used to manage SCSI RAID arrays too, so don't
be surprised when you see numbers higher than four in that part. Hit Next again,
and it takes you to the final array creation window, in which you can select the
stripe size. The options are 8KB, 16KB, 32KB, 64KB, and 128KB, with the default
being 64KB. Generally, you should only use 64KB or 128KB as the smaller stripe
sizes are just too small. You can see that the performance settings part is
grayed out. As this section is used for managing the controller's cache DIMM, my
assumption is that it is not configurable on the AAA-UDMA simply because it's
unlikely you'll have more than one array, so the hardware defaults for cache
settings are probably used.
This function would be more important on SCSI
RAID controllers, which can often have up to 128MB or more of cache available
and which may also control several large RAID arrays at once, which may be used
for different functions. This window also allows you to select spare drives from
those not selected for use with the array itself. Spares are simply extra,
unused drives that are available to take over for failed drives. For example, if
you have four drives on your controller and want to really, really make sure
your data isn't lost, you could create a RAID 1 array with the first two drives,
then use the other two as spares. If an array member fails, one of the spares
immediately takes its place, so in this situation up to three of the four drives
could fail and the data would still be fine.