Adaptec iSA1500
This iSCSI-based storage array should prove cost-effective
Roger Howorth, IT Week 14 May 2004
Announced last autumn and delivered this spring, the iSA1500 is Adaptec's first iSCSI-based storage device. This 1U (1.75in) rack-mounted appliance is also one of the first signs of Adaptec's transformation from a supplier of SCSI chipsets to a vendor of storage systems. IT managers should note the product and its price, because as one of the first iSCSI servers to market it could become an unofficial benchmark against which others will be judged.
For example, Adaptec supplies a special utility that makes it extremely easy to manage iSCSI storage allocations to servers running Microsoft Windows. The utility is not essential, but it integrates with the Microsoft DiskPart service that is available for Windows 2000 and included with Windows 2003. DiskPart provides the API that enables the Adaptec agent to automatically provision storage from the management console. Adaptec said it is working on a similar utility for use with Linux servers.
In IT Week Labs we found that the performance of iSCSI systems does not yet compare with that of storage area network (SAN) kit. So high-performance servers would be better served by other technologies. However, iSCSI is a strategically significant technology that delivers the benefits of traditional SANs to low-cost, low-performance server systems. In this context the iSA1500 is a ground-breaking product that comes with some excellent tools to remotely provision iSCSI storage.
The hardware comprises a 1.6GHz Xeon chip, 1GB of RAM, two 1000BaseTX Ethernet ports for iSCSI data, and a separate 100BaseT port for managing the server. A myriad of Raid configurations are supported, including the popular 5, 0 and 10. Clearly, the available storage capacity varies depending on which Raid levels are used.
Four 250GB Sata hard disks are used, which are not fitted during transit. Adaptec said the mechanical characteristics of the Sata connector are not strong enough for drives to be transported while in place. However, the drives use hot-pluggable mountings and can be fitted in seconds. Overall, initial installation was easy and took less than an hour, although better labelling on the various Ethernet ports would have improved matters slightly.
With the hardware installed, we needed to configure the disks into a number of storage pools - each pool uses a specific Raid level. In our tests we created a single Raid 5 pool using all the disks, resulting in a pool of 750GB capacity. Pools are further divided into iSCSI targets, so we created several targets of 4GB each and allocated these to various iSCSI initiators.
Individual iSA1500s can be controlled using a serial or Ethernet connection to the built-in management tool. Either way, the Adaptec console provides a flexible environment that might be preferred by Unix and Linux administrators. A more graphical environment is provided by the web-based management system, but this runs only on Windows systems. Even so, the tool sets the iSA1500 apart from the other iSCSI storage systems we have seen. For example, having installed the free Microsoft iSCSI Initiator software and Adaptec agent on a remote Windows server, we easily moved storage between servers by clicking on the server that was to relinquish ownership of the storage device. This displayed a context-sensitive menu that included an option to allocate that storage to another server. These operations can be scripted to occur at predefined times.
We found a few shortcomings with the less frequently used functions in the management console. For example, reallocating storage from a server that is not running is a relatively complex process.
Price: £5,555 + VAT
Contact: Adaptec 01276 854 500
© 2004 Incisive Media Investments Ltd