Raidtec FibreArray and Raidtec FlexArray UltraRAID Systems

Raidtec addresses your SCSI and fibrechannel disk storage needs

I'm always looking for bigger, faster storage systems because I frequentlyrun out of room on my system, and I often come across new applications that needbetter disk performance than I have. Raidtec offers two storage systems thataddress both of my needs:

(For more information on the differences between fibre channel and SCSIsystems, see my article "Fibre Channel, SCSI, and You," September1997.)

Each disk subsystem comes with an enclosure, hard drives, a controllercard, cables, and software. The enclosure is a fault-tolerant towerconfiguration with room for seven industry-standard, bus-isolated, hot-swappablehard drives. It also uses redundant, hot-swappable fans and power supplies tomake it even more resilient. The enclosure sits on lockable wheels. It is 17.4inches tall, 8.7 inches wide, and 20.6 inches deep and weighs about 45 poundswithout the hard drives installed. Raidtec makes a rack mountable version, oryou can purchase a rack mounting kit and convert the tower system to a rackmounted system later.

An Environment Array Manager (EAM) is built into the enclosure. EAMmonitors the status of the drive bays, power, fans, and internal temperature. Italso controls the built-in LCD display and the light-emitting diodes thatindicate the status of each drive. A four-button touch panel with an LCD statusdisplay is conveniently located on the front of the unit.

You can chain multiple enclosures of the same type (SCSI or FC-AL) togetherand manage them with the RAIDman LITE software, which is included. The softwarelets you monitor and perform diagnostics on a given hard drive or the entireenclosure. You can even perform these tasks from a remote workstation.

Adding Fibre to my Diet
The FibreArray FC-AL disk subsystem that I reviewed used an EmulexLightPulse PCI Fibre Channel Adapter connected to the FibreArray fault-tolerantdrive enclosure. (For information about the adapter, see "EmulexLightPulse PCI Fibre Channel Adapter.") The enclosure was loaded with sevenSeagate 9GB fibre channel hard drives, giving a total of 63GB of storage spacewithin one cabinet. You can chain 16 FibreArray enclosures together, which letsyou have 112 drives online at once. This setup will give you more than 1TB ofonline storage.

The FibreArray disk subsystem achieves data rates of 106MB per second. Youcan double this rate by adding a second port bypass module. You can connect thesubsystem to any FC-AL compliant controller. FC-AL lets you connect up to 126devices in a single loop and string them up to 98.5 feet apart. Alternatively,you can use optical cable to string the devices as far as 6.2 miles apart.

Setting up the FibreArray disk subsystem was easy. I installed the Emulexadapter in the server, connected the FibreArray to the adapter, booted theserver, and installed the Emulex adapter drivers. To complete the setup, I usedNT's Disk Administrator to format the hard drives.

I performed several tests on this system. Not only was FibreArray easy touse, it was also fast and effective. I did, however, find one drawback: To getRAID capabilities, you must use the RAID software that is built into NT. This isa disadvantage compared to hardware-based RAID solutions. But Raidtec iscorrecting this situation by releasing the Raidtec Fibre RAID-PCI controllerthis month.

My SCSI Story
The FlexArray UltraRAID disk subsystem I reviewed included the FlexArrayfault-tolerant drive enclosure, the Raidtec UltraRAID controller, and sevenSeagate 2GB UltraWide SCSI-3 hard drives. The enclosure supports off-the-shelfstandard SCSI disk drives. You can connect two enclosures together to theUltraRAID for improved manageability and increased online storage. The largestdrives that you can install are 9GB drives, so you can get a total of 63GB ofonline storage with one enclosure and 126GB with dual enclosures. You caninstall any industry-standard Single Architect Drive in this subsystem.

The RUAC RAID controller is a PCI card with two ultrawide SCSI-3 connectorsand a serial connector for configuration and monitoring. It uses two card slotsand has an Intel i960 processor and a SIMM socket for cache RAM. The controlleralso has an onboard parity generator that calculates parity data on the fly,boosting performance over other RAID controllers.

The FlexArray disk subsystem was as easy to install and use as theFibreArray disk subsystem. I installed the RUAC RAID controller, connected it tothe FlexArray, booted the server, and installed the RAID controller drivers. Ithen configured the drives using Raidtec's RAID configuration software. Theconfiguration software is a DOS-style utility that works reasonably well. AfterI partitioned the drives using the configuration software, I used NT's DiskAdministrator to format the partitions.

Which One?
Both of these systems are definitely worth investigating because of theirhigh performance, ease-of-configuration, diagnostic functions, andfault-tolerance abilities. The FlexArray UltraRAID is worth considering if youare on a budget and don't need the flexibility that fibre channel offers. If youneed the fastest system possible or the flexibility of fibre channel, theFibreArray is a better choice.