Six iSCSI SANs unleashed
Adaptec, Celeros, EqualLogic, Intransa, NetApp, and Rasilient move our megabytesFollow @pvenezia
Network Appliance is an old hand at big storage. Before the advent of the SAN, NetApp made its name on true storage appliances, providing NFS and SMB (Server Message Block) file sharing to the network in stand-alone systems. Since moving into the SAN arena, the company hasn't forgotten its roots. The NetApp FAS3020c builds on this heritage by providing NFS and CIFS access to storage volumes via NIS (Network Information Services) and Active Directory integration and by serving as an iSCSI target. In this way, it's possible to configure all your desktop file-sharing needs and server-centric storage requirements from a single box, removing the need for a separate file server. This capability is quite worthwhile for many shops, and it proves to be a strong selling point. My tests, however, focused on the iSCSI functions alone.
The FAS3020c consists of a 3U controller set with eight NICs and redundant power and a 3U fiber-attached disk shelf. Multiple shelves can be connected to a single controller to scale out the array, but even at its smallest, it will consume 6U. The hardware is refined and even attractive, with a central backlit LCD panel providing instant status information and I/O-per-second statistics.
Configuring the FAS3020c was simple and straightforward, requiring a quick pass through the console to perform the initial setup and then work in the FilerView Web application to complete the installation. FilerView is a standard Web front end; it ran well under every browser I could throw at it. The interface takes a wizard-based approach that can get in the way when you're making major changes to the configuration, but it does help prevent you from losing your way or misconfiguring the SAN.
The FAS3020c uses the concept of volume aggregation. Essentially, the array is configured as a single raw volume that can then be divided into smaller volumes to present to servers, or to share via NFS or CIFS, or both. This abstraction layer makes dynamic volume growth simpler to manage. As do most of the other products reviewed here, the FAS3020c provides both CHAP and IQN access controls to ensure proper initiator control, with FilerView providing a relatively straightforward method of defining initiator groups that are then assigned to LUNs for volume presentation. This grouping method is found on many other SAN arrays, and it makes administration much simpler. All in all, it took about 20 minutes to get from box to bytes.
The raw performance of the FAS3020c didn't match up to my expectations. It definitely has punch, but I couldn't push it much past 60MBps in the read tests, and writes dropped below that. This is likely due to the dual-dialect nature of the solution, but I'm reasonably sure that some tweaking could improve those numbers.
The clustering capabilities of the FAS3020c are something to behold. Of all the redundant solutions in this test, NetApp's was by far the most complex, requiring specific Fibre Channel loop wiring between the controllers and disk shelves and two massive clustering cables that connect the controllers. Maybe every vendor should go so far: The result was completely seamless fail-over, the test unit accomplishing a full takeover of a failed controller without a hitch.
The replication features in the FAS3020c offer the ability to replicate volumes to other arrays on an immediate or scheduled basis, functioning almost exactly like a Unix cron job.