3PAR for the high-performance storage course

Easy-to-manage InServ Storage Servers lead the pack

Most storage systems are either appliances -- easy to set up but limited in capacity and performance -- or large, high-performance systems that take a week’s training to configure and run. 3PARdata is aiming for the middle with its InServ S400 and S800 Storage Servers, which combine easy provisioning with very high performance and data management features.

Rack ’em up

The S400 and S800 differ only in the number of controller nodes and total capacity. The S400 supports two or four controller nodes and as many as 1,280 drives for a capacity of 192TB. The S800 doubles that, with as many as eight controller nodes and 384TB.

The systems are extremely modular: a drive chassis holds as many as 40 drives and expands in small increments. Each half of a chassis holds fully redundant power supplies and FC (Fibre Channel) loops. You can start with one or two controller nodes and one or two drive chassis, then add more as bandwidth and redundancy requirements grow.

All InServ hardware is both highly fault tolerant and very high performance. There are multiple paths to every drive chassis and storage controller, but these are not used simply for redundancy and fail-over -- they are set up as a full mesh backbone. As in an active/active system, all paths available are used at all times, providing a peak interconnect bandwidth of 28Gbps with eight controller nodes. Storage traffic is automatically balanced across available data paths to prevent bottlenecks.

The InServ Storage Servers partition drives into 256MB “chunklets” that are the basic building blocks of virtual volumes. Chunklets are the same size no matter what drives are installed in the system, and are pooled into virtual volumes so a given volume can be spread across dozens or even hundreds of drives.

One of InServ’s most valuable features is thin provisioning, which allows an administrator to create a virtual volume that’s easily expanded as needed. A volume is given a virtual capacity of a few terabytes and a starting physical capacity of only a few gigabytes, and the system automatically expands the volume when utilization of existing physical space reaches a threshold.

Streamlined setup

Setting up the InServ system is a breeze, even for a systems administrator without much storage training. During my testing at 3PARdata’s corporate training center, I easily initialized the system, set up volumes, changed RAID levels, and performed system maintenance without training or help from support staff. That’s unusual in a system with this level of fault tolerance, capacity, and performance.

I tested an S400 model with two controller nodes and two drive chassis, each with 40 drives. Software included the 3PAR InForm Operating Suite: InForm OS, Access Guard & Full Copy, 3PAR System Tuner, and 3PAR Virtual Copy DBA, which includes 3PAR Virtual Copy. Servers attached to the storage server included Windows, Solaris, and Linux hosts.

The clear, well-thought-out GUI makes virtual volume creation and management extremely simple. Creating a basic volume is easy, and if you want to specify low-level parameters, such as creating a volume that uses only the fastest parts of each disk, the GUI makes finding the right menu items simple.

You can restrict virtual volumes to specific hosts, or to specific FC ports if you don’t know the worldwide names when you set up the volume. For highest security, you can even restrict a volume to a specific host on a specific port. Volumes are automatically striped across all available drives and controllers by default, although a volume can also be restricted to a particular controller or drive chassis.

Experienced administrators will find the CLI responsive and easy to use. However, a few commands are available only through the CLI, because 3PAR integrates new features into the CLI before adding them to the GUI.

Service with a smile

A common storage-admin headache involves providing different service levels to specific hosts. When a project becomes more or less important, changing the service level usually requires backing up the existing volume, creating a new volume with the new service level, moving files, and disrupting services during the move.

Thankfully, InServ’s speed and flexibility ease that pain. I placed a load on a volume using Iometer, then changed the volume type from RAID 5 to RAID 1 and tuned the volume so only the fastest parts of each drive were used -- all without interrupting the availability of the volume. During this test, the volume reached a threshold of 80 percent of capacity and automatically expanded without disrupting service or performance.

The InServ also makes very flexible copies of data (full copies or snapshots). These can be cascaded, and at any point in a chain of copies, if you promote a copy to be the “base” copy, all copies up the chain will automatically reorganize to reflect the new control point. This makes it easy to restore missing or corrupted files and start over with corrected versions.

Creating copies and promoting or synchronizing them is extremely fast -- promoting a 2TB volume took me about two seconds. Remote copies can also be made to a second InServ system via IP.

With very high performance, reliability, and an innovative feature set, as well as an easy-to-use interface, the InServ S400 offers a lot for a price lower than many comparable systems. The only downside for large organizations is that 3PARdata is a smaller company with limited service capability, although its remote service option should make most on-site service calls unnecessary.

InfoWorld Scorecard
Manageability (20.0%)
Capacity (20.0%)
Reliability (20.0%)
Speed (20.0%)
Value (10.0%)
Interoperability (10.0%)
Overall Score (100%)
3PAR InServ S400 9.0 9.0 9.0 9.0 8.0 9.0 8.9