Product Reviews

Fujitsu Siemens has always maintained a strong storage portfolio, and it claims the latest SX88 is its best FibreCAT ever. It reckons it's the fastest as well, because its RAID controller has been beefed up with an improved specification.

The SX88 represents the pinnacle of the FibreCAT disk-array family and is aimed at SMBs running applications such as high-volume backup, databases and streaming media, and looking for high-speed 4Gb/sec FC SAN connectivity plus good expansion potential.

This 2U chassis is extremely well constructed. There's room for 12 hot-swap hard disks, and the SX88 accepts SAS or SATA, or a mix of both. Fault tolerance is extensive, with the chassis offering dual redundant RAID controllers plus dual combined fan and power supply units.

Expansion options are good, with the array supporting the latest high-capacity drives, while the single SAS port on the RAID controllers allows you to increase to a maximum of five enclosures.

The FibreCAT's RAID controllers offer a couple of unusual features. The SX88's FibreCap technology replaces battery backup packs with a combination of capacitor and CompactFlash card; if there's a power failure, the cache contents are written to the card.

When power is restored the capacitor takes less time to recharge than a standard battery pack and can provide full protection much quicker. Next up is FibreCache, which provides a high-speed, direct link between two controllers.

Data written to one controller is synchronously mirrored to the other and it aims to improve general performance by reducing internal system traffic between the controllers.

For installation, you can use a serial port connection to the CLI, but don't lose the supplied cable as the small port on the controller is proprietary. We found it just as easy to point a web browser at the unit's default IP address, where we were greeted by a well-designed management interface.

You start off by creating virtual disks, or vdisks, where you select the member drives, decide on a RAID array and assign

During vdisk creation, you select the preferred controller and the number of volumes it should have.

You can leave the controller to create equal-sized volumes, and then you name them and decide if they should be available to all hosts. Volume sizes can be expanded on the fly, while snapshots are used to take point-in-time volume copies and store them in a snapshot pool on the appliance.

The SX88 supports Microsoft's MPIO (multipath I/O), which uses multiple hardware components to create redundant paths from hosts to storage volumes. Fujitsu provides its DSM (device specific module) as standard.

For testing, we used a Boston Supermicro dual 3GHz Xeon 5160 server running Windows Server 2003 R2 and equipped with an LSI Logic 4Gb/sec dual-port HBA.

Our initial speed test involved creating a dual-drive RAID0 striped vdisk with one volume that we made available to all hosts. This was duly picked up by the server and presented as a local 300GB hard disk.

Be careful when you configure the array's host ports - our first Iometer test run returned 195MB/sec, which had us scratching our heads until we found that the ports don't support auto-configuration and were hard set to 2Gb/sec.

With the speed upped to 4Gb/sec, Iometer reported a sizzling raw throughput of 370MB/sec when configured with four disk workers, 64KB request sizes, 100% sequential reads and 100 outstanding I/Os.

We then created another dual-drive striped vdisk with a single volume. We assigned this to a second Boston dual 3GHz Xeon 5160 server, which we direct-attached to the second FC port on the array's RAID controller.

With Iometer running on both servers, we saw a raw throughput of 510MB/sec, showing there was some contention for resources on the single RAID controller. We also tested MPIO operations.

Although the CLI is a bit basic, we set up dual FC connections from one server with a weighted policy applied. We started Iometer up across both test volumes and saw a throughput of 480MB/sec.

We pulled one of the FC connections and watched speed drop to 368MB/sec, but the connection to both volumes wasn't lost. We plugged the FC cable back in and transfer rates climbed back up again.

One of our biggest issues with FC SANs is the high price certain vendors charge, which has pushed fibre channel out of the reach of SMBs on strict budgets, but Fujitsu Siemens has sensibly priced the SX88. Performance under load could be better, but expansion potential and features are very good.