Exabyte VXA-172 Packet Tape Drive review
Traditionally, whenever a company’s wanted to increase backup capacity, it’s had to upgrade to the next-generation tape drive. Exabyte’s new VXA-172 brings an interesting and unique alternative: you purchase the tape drive and, when you’ve outgrown its capabilities, you simply upgrade its firmware. In a matter of minutes, you now have the same physical tape drive but a doubling in capacity.
Essentially, the VXA-172 is a VXA-320 but with a firmware version loaded that only supports Exabyte’s X6 and X10 media, which offer 40GB and 86GB native capacities respectively. Once the upgrade has been performed, the drive is effectively turned into a standard VXA-320 drive. Speed remains exactly the same, but the drive can now use the X23 cartridges, which deliver a 160GB native capacity, and it’s also read and write backward compatible with VXA-2 and VXA-172 media. If you have any VXA-1 media then lose it, as neither incarnation of this drive can read it and will automatically eject these older cartridges.
Naturally, the VXA-172 is endowed with Exabyte’s three packet-writing technologies, which are designed to provide reliable data restoration. These allow data to be broken down into packets and read back in any order, as they’re reassembled in the drive’s buffer before being sent to the host. The drive can adjust tape speed to match the data flow, and data can be scanned and rewritten if an error is detected.
For performance testing, the drive was connected to a Supermicro dual Xeon system running Windows Server 2003. Computer Associates ARCserve 11.5 was selected as the test backup software and we used a 7.5GB mixture of data. ARCserve had no problems identifying the drive. We asked it to back up and verify the test data and then restore it back to its original location. We found backup operations for the VXA-172 were as quoted, with the test data secured at a rate of 12.1MB/sec. However, speed did drop for data verification, with ARCserve reporting 9MB/sec, and this remained constant during the restoration task.
The upgrade process is simple, as you purchase a key and use the bundled Exabyte VXA Tool to perform the update. Remember this is a one-way trip – once you’ve upgraded, you can’t reverse it. It only takes a few seconds and then the VXA Tool identifies the drive as a VXA-3 model. The first evidence of the upgrade working is when you load an X23 tape. With the VXA-172, it will simply eject it, whereas after the upgrade it’s happy to use it. Speed is unaffected, as running the same backup, verify and restore tests on ARCserve returned 12.1MB/sec, 9.1MB/sec and 9MB/sec respectively.
As opposition to the DAT72 tape drive, the VXA-172 is a strong contender. It costs around the same but offers double the capacity and four times the native performance. The DAT cause isn’t helped by the delayed launch of DAT160, as our sources tell us this has been put back to possibly as late as September this year. From a cost perspective, the VXA-172 looks a sensible alternative, as the combined cost of the drive plus upgrade equals less than a standard VXA-320 drive, and the improved capacity will knock the increasingly nebulous DAT160 into a cocked hat.