Like it or not, the shift to Thunderbolt is underway. The connection is extremely flexible, allowing for video and data to co-habitate on the fast-speed bus. The problem is, the introduction of new ports doesn't preclude the need to use old ports. Highpoint has a solution for those eSATA drive cases in the Thunderbolt 2 RocketStor 6324L host adapter for eSATA devices. Bridging devices for older connectors can be expensive, and sometimes its worth it to replace the enclosure instead -- does the value equation hold up for this speed-oriented adapter?
First of all, specifications. The RocketStor 6324L features dual Thunderbolt 2 ports, and a single Mini-SAS port. The SAS port is capable of supporting up to four 6Gb/s eSATA drives, or cases. The device isn't a RAID bridgeboard, and that is best left to the enclosures or the OS itself, user needs depending. A larger 6328 model has a pair of SAS ports, supporting up to eight eSATA drives, with proper cabling. HighPoint claims the device can push up to one gigabyte per second of data moved across the device. As advertised, the device does not support port multiplication. An additional two cables are required to utilize the device -- both a Thunderbolt 2 cable and sell as either a Mini-SAS to Mini-SAS or MiniSAS to quad-eSATA. We tested both the MiniSAS options.
We tested the 6324L with a new Mac Pro connecting to nearly 80 different enclosures, ranging from single-drive models to multi-bay towers. Sure enough, towers that need port multiplication to function only show the first addressable drive to the operating system -- but we already knew that. Speed wise, with four LaCie 2TB 7200RPM drives attached to the 6324L, we hit 1086MB/s write speeds with large files, and 1212MB/s read speeds. Happily, the adapter over-performs.
We've got SSDs about that we're reviewing, so we replaced the hard drives with SATA-3 SSDs, all known for speed. Speeds did climb a bit, but not as much as the SSDs are capable of, suggesting that loaded with platter drives, the speed of the bridge is about at maximum. Large file transfers grew to 1094MB/s, with 1218Mb/s read.
With smaller files, which is more indicative of real-world performance, the hard drives pushed 663MB/s and read 790MB/s. The SSDs fared better in the speed trial as is expected with SSDs and small files, with 1044MB/s write, and 1102MB/s read. Native SAS cases (generally found in enterprise) performed at approximately the same speeds with all testing.
On the subject of port multiplication -- port multiplying cases take a single eSATA connection, and span it across a couple of drives. With a multi-drive case using port multiplication and not a full-fledged RAID controller, only the first drive will show. However, if a case presents a single logical drive to the operating system, then the entire volume is accessible, as the controller in the case is governing the addressing of the drives and not the 6324L. So, we don't think the lack of SATA port multiplier support is a problem with the adapter at all, given what it sets out to do -- deliver the highest speed possible through older eSATA connectors.
Thunderbolt daisy chaining isn't an issue. We connected a Mini DisplayPort monitor downstream of the 6324L, and had no issues. Other Thunderbolt adapters were tried, also with no problem.
We all knew that there'd be a migration period from eSATA to Thunderbolt and USB 3.0. The RocketStor 6324L is Thunderbolt 2 and unapologetically fast, as it was designed to be so. It preserves investments in older cases, as RAID Thunderbolt is still very, very expensive. No, there is no port multiplication support, but you buy the 6324L for speed, not to utilize the cheap cases. We'd like to see some cables included, our same complaint with the Thunderbolt drive dock from Highpoint we tested, but that's not a showstopper -- if you buy the 6324L, be aware that you need two cables in addition to the adapter itself!