Reviews

posted on 05 June 2008 19:56

Summary: A sophisticated solution for managing ILM strategies with slick automated data classification and migration technologies that could make big savings on network storage costs.

Pros: Automatic drive identification, unique block level data migration, thin provisioning, FC and IP SAN support, good performance.

Cons: Replacing the FC arrays with SAS would make first tier storage more cost-effective.

An ILM (information lifecycle management) strategy can make the best use of network storage but for it be effective all business data needs to be classified, and Compellent’s Storage Center offers a unique solution that fully automates this process.

On review is Compellent’s latest ILM bundle which comprises a rack-mount controller appliance partnered by two sixteen-bay drive arrays. The first array comes with an octet of 400GB high-performance 15K FC drives for first tier storage whilst the other provides eight 500GB SATA drives for a tertiary tier. A secondary tier can be added if required and would comprise an array with 10K FC drives.

Compellent’s DBA (dynamic block architecture) automates data progression and works at the block level where it uses metadata to track the location of each data block. As data blocks become less used they are migrated down through each tier. However, it’s not a one-way trip as data blocks that improve their popularity rating will be automatically migrated back up the through the tiers.

The controller in the ILM bundle comes equipped with dual-and quad-port FC HBAs to provide array connectivity and support for FC SANs. We were also supplied with an optional dual-port QLogic iSCSI HBA allowing us to test IP SAN features. Compellent’s new web management interface improves installation considerably and also offers plenty of quick start wizards. You can go for multiple RAID arrays in each tier but don’t worry about disk categorisation for each tier as this is done for you.

DBA uses Disk Folders which can contain any or all drives and comprise a mix of FC and SATA. Within each one you create virtual volumes which are then assigned to your FC or IP SAN hosts. When configuring data progression all you need to decide are the number of days a block must remain unused before it is migrated to a lower tier and a ratio that determines how quickly it is moved back up.

The Storage Center is no mean performer as our lab tests showed it delivering raw read speeds of 113MB/sec over iSCSI for one host and a cumulative 198MB/sec with two hosts connected. Performance over FC is nothing to sniff at either with a single 4Gbps direct attached host reporting an excellent 350MB/sec read speed.

There’s much more on the storage menu as thin provisioning allows you to create virtual volumes that are larger than available physical capacity. DBA keeps an eye on used physical storage and dynamically allocates blocks as it increases in size. Compellent’s replays use less space than the more common snapshots when creating point-in-time backups and the new Fast Track feature places frequently accessed blocks on the outside on a disk drives’ platters for faster access.

Compellent’s DBA neatly automates data classification and migration allowing you to get the best value from your network storage. The Storage Center is easy to deploy and also offers sophisticated thin provisioning and data backup plus a range of replication options.

<sup>Product: Storage Center
Supplier: Compellent Technologies 01494 582041
Internet: www.compellent.com
Price: ILM bundle from £30,000 ex. VAT

Tester: Dave Mitchell of Binary Testing Ltd,
Unit 33, Newhaven Enterprise Centre, Denton Island, Newhaven, East Sussex, BN9 9BA</sup>