MPC aims for SAN supremacy

DataFrame 310fc SAN array stacks up well despite slow rebuilds

MPC has long been a contender in the desktop and server market, but always sitting just behind the other players, such as Hewlett-Packard, Dell, and IBM. The MPC DataFrame 310fc may help change that; MPC's latest SAN array, combined with Spheras Storage Director from Eurologic (recently acquired by Adaptec), is a worthy competitor.

The solution is relatively OS-agnostic, supporting Red Hat Linux, Windows, Solaris, SCO Unixware, and Novell with compatible HBAs. The lab’s Qlogic QLA2213 FC (Fibre Channel) HBAs had no problems under Windows and Linux. Housed in a 2U rack-mount chassis containing redundant RAID controllers, 256MB cache, redundant 2Gb FC I/O modules, redundant power supplies, and 14 drive slots, this array will fit nicely in many infrastructures.

The DataFrame 310fc has more than the mid-size datacenter in mind, however. The solution will scale to a surprising 16.6TB of addressable storage from a single pair of controllers with 146GB disks, expanding to eight shelves. On the reliability side, the solution comes with standard redundant power supplies, fans, and I/O modules, with a redundant RAID controller option.

Although there were a few minor software glitches during installation, the DataFrame 310fc fared well in the lab, surpassing my expectations.

Out for a Test Drive

Hardware used in a SAN array is integral to the overall performance, but the SAN management tools are equally, if not more, important. In MPC’s case, Spheras Storage Director handles these tasks for the DataFrame 310fc. The wizard-based installation of Storage Director is identical across all platforms, as is the application itself: The server is installed as a system service or daemon, with the Java Web client utilizing a local Web server to present the administration interface to a remote browser. In a pure Windows environment, this means installing IIS on at least one server in the SAN. With Linux or Solaris, it requires the Apache Web server.

The installation on Windows Server 2003 was fairly clean and straightforward, requiring a Virtual Directory configured under IIS to link to the Web root of the Storage Director client. Installation on Linux was more problematic, and wholly related to a bug in the installer that presented an error dialog regarding insufficient privilege levels, even though it was run as root. MPC sent a new installer, and the subsequent installation was a breeze -- the Linux installer even correctly modified the Apache configuration, although I wasn’t pleased that Apache was restarted without warning.

Host-based administration consoles can present a liability, in that the management host must be functional to view or modify the configuration of the array. Should a server fail, the array configuration is not accessible until the server software is installed on another server on the SAN. However, installing the configuration server components on every server on the SAN is also detrimental, as it requires both a Web server and accompanying Storage Director service be installed on additional servers.

That said, the Storage Director management interface is clean and intuitive, permitting wizard-based or manual array and LUN (logical unit number) configuration. The interface mimics the Microsoft Management Console, displaying a hierarchical tree of configuration and management options, from chassis health to array and logical disk configuration. Events are presented well, and management of the array is accomplished easily. It would be nice to see a host-independent array configuration interface, and MPC does in fact offer a controller with direct Ethernet access (although it was not included in the review unit).

Redundant server connections to the array are supported via PATHpilot, which handles Windows SAN problems dealing with two paths to the same volume. Pathpilot will monitor the links to the array and force one link inactive unless the other link fails, which provides redundancy at the server level.

Performance Play

Configured with a seven-spindle RAID5 array, the DataFrame 310fc performed very well during the Windows throughput testing, averaging 180MB/s buffered read, 100MB/s sequential read, and 36MB/s random read with a 1GB file size. Write testing averages were 160MB/s buffered, 148MB/s sequential, and 22MB/s random write. The testing with bonnie++ under Linux rendered similar results, showing a very slight performance degradation, but all within the margin of error. All testing was done with read and write caches enabled.

One knock on the performance side was the time taken to rebuild a degraded array. A RAID5 array of 360GB composed of six 72GB drives took two hours and 30 minutes to return to an optimal state following a forced drive failure. This isn't a terrible time, but it could certainly be faster, since performance is significantly reduced during a rebuild period. As a comparison, the Dell CX200 rebuilt an identical array in just over one hour.

Overall, MPC has a solid SAN array in the DataFrame 310fc, packing performance, scalability, reliability, and suitable management tools into one tight package. The $46,939 price, not including the SAN switches, is higher than many lower-end arrays, but with MPC’s solution you get much greater scalability for your storage buck.

InfoWorld Scorecard
Value (10.0%)
Configuration (20.0%)
Management (20.0%)
Performance (30.0%)
Scalability (20.0%)
Overall Score (100%)
MPC DataFrame 310fc 8.0 8.0 8.0 9.0 9.0 8.5