OmniRAID Cluster Array

Configure your storage space in any environment

In the computer industry, flexibility is imperative. The ability toconfigure your storage space in a changing environment is a necessity. Moststorage products let you configure storage space a few ways, but StorageComputer's OmniRAID Cluster Array lets you configure storage space in almost any environment.

With the OmniRAID Cluster Array, you can partition storage space onto twoor more disks with nonconcurrent access from multiple hosts. You can configurethe disks into one large hard disk with concurrent access from multiple hosts.However, until a distributed lock manager is available for Windows NT, thisconfiguration won't work. You can also partition the space onto two hard diskswith concurrent access from two hosts, which is what I did for my tests in theWindows NT Magazine Lab. To conduct clustering tests, I needed toconnect two identical hard disk partitions with two SCSI host adapters from eachhost into the rear panel of the OmniRAID Cluster Array.

Configuring the System
To configure the OmniRAID Cluster Array, you need to set up a configurationdisk. You must boot up the OmniRAID Cluster Array using this disk each time you use the array. You must also configure the OmniRAID Cluster Array cabinet. The OmniRAID Cluster Array cabinet relieves the storage space problem all networks experience and provides the data protection all networks need. The user's manual outlines these configuration procedures. However, I would have preferred to have a wizard walk me through each step.

OmniRAID Cluster Array uses RAID 7, a more advanced version of theindependent access array (RAID levels 4, 5, and 6) concept that assists in datathroughput. RAID 7 is an asynchronous access level that, like RAID 4 and RAID 5,uses a singular parity stripe to protect data stored across multiple datastripes within the same data transfer. RAID 7 alleviates the write bottleneckthat characterizes RAID 4 and RAID 5. In addition, each member of a RAID 7 arrayhas a dedicated channel of memory and CPU resources, resulting in faster I/O.

Setting Up the System
To set up the OmniRAID Cluster Array, I ran the RAID 7 diagnostic disk,which tests all system components. Next, I inserted the RAID 7 Storage OperatingSystem (SOS) disk and rebooted the cabinet. The product performs a physicalresource audit that it writes to the SOS disk. When the audit is complete, thesystem writes a configuration file that specifies the number of drive and hostchannels and the amount of available disk space. I removed the SOS disk andinserted the RAID 7 configuration disk. At the appropriate prompt, I reinsertedthe SOS disk and the Main Configuration menu appeared. This DOS-based menudoesn't offer online help. However, the user's manual provides explanations forthe various menu parameters. I used the configuration program to set twopartitions and their controlling host channel numbers, SCSI target ID numbers,and Logical Unit Numbers (LUNs). I wrote the configuration to the bootup diskand kept a backup copy.

I rebooted the cabinet with the SOS disk, and my parity drive started itscreation process. When this process ended several hours later, the OmniRAIDCluster Array operated like a SCSI drive. I connected the ends of two SCSIcables to the Host 1 and Host 2 connectors inside the cabinet and the other endsto Adaptec 2940UW SCSI adapters in my test computer. After I rebooted thecomputer, I configured the adapters, rebooted again, and logged on to NT. Iopened the Disk Administrator, and my two 67.831GB partitions were ready forformatting. After I formatted the partitions, I copied data to them, and theyoperated like RAID drives.

You can connect the OmniRAID Cluster Array to four host computers orchannels simultaneously. The OmniRAID Cluster Array can also expand to supportas many as twenty-seven 9GB hard disks. An i486DX2-66 processor with 2MB of RAMcontrols the OmniRAID Cluster Array's overall operation. The OmniRAIDCluster Array's redundant power supplies let the system continue when one of thepower supplies fails. The configuration and use of the OmniRAID Cluster Array isalmost limitless, although the cabinet's size (78" * 24" * 36")might limit where you can put it. (The system is available in various sizes andconfiguration capacities. You can also adjust the number of host connections.)

Testing, Testing
I used Iometer to test my newly created drives and OmniRAID Cluster Arraycontrollers. Iometer provides disk I/O subsystem measurement andcharacterization for simulated users (workers) operating a particular system(i.e., single or clustered). Iometer calculated the I/O per second and theaverage and maximum response times in milliseconds (ms) for the OmniRAID ClusterArray. (You can download Iometer for free from Intel's Web site athttp://developer.intel.com/design/servers/devtools/iometer.)

I chose a 30-minute test with one worker generating the load. The testcompleted in approximately 35 minutes. The I/O per second was 58.22, and theaverage and maximum response times were 9.2ms and 38.45ms, respectively. I ran the test four times, and each time the results were within 1 percent of theoriginal results.

A Worthy Storage Solution
The configuration process for the OmniRAID Cluster Array is not as quick asother RAID arrays the Lab has tested, but it is just as thorough. Despiteinitial difficulties with the bad drive and array board, the OmniRAID Cluster Array worked well (although a GUI tool to ease navigation would have been helpful). The OmniRAID Cluster Array's RAID 7 technology offers additional data protection and increased storage space, and the system's four-host expandability makes it a worthy storage solution.