Performance and reliability have always been key weaknesses of tape backup devices, and companies are often forced to sacrifice one virtue for the other. Producing more reliable double-copy backups, for example, could mean accepting slower and longer backup sessions.
Much of the problem stems from the fact that, although most backup devices are loaded with multiple tapes, only one tape is used at any given time. The others sit idle and their potential performance is therefore wasted.
That's where a device such as Maxoptix's new StreamIT comes to the rescue. StreamIT includes a set of Sony AIT (Advanced Intelligent Tape)-2 drives and a powerful RAID controller, made by Ultera to allow these multiple drives to work as one, thereby delivering increased capacity, performance and reliability.
Overall, StreamIT delivers a performance improvement that would be otherwise unattainable, even if you were to switch to a faster tape technology such as Super DLT, LTO (Linear Tape-Open) or Sony's upcoming AIT-3.
In testing, we were impressed enough with the StreamIT device to award it our top score of Excellent. Our only reservation was that StreamIT is compatible only with Sony AIT-2 tapes.
Quadruple the quality
The StreamIT device does not actually increase the 100GB capacity of AIT-2 media, nor does it improve speeds beyond the native 6MBps. It does, however, allow you to write data simultaneously across four tapes, thus bringing out the performance in each of them.
The results are numerous: as much as four times the backup performance of competing products, better reliability of backup media, easy administration and the flexibility to deploy multiple units for additional scalability.
StreamIT connects to your servers via either a fast, 80MBps SCSI connection or through a fibre channel link. Those two interfaces make it easy to deploy the unit in both legacy and advanced environments.
We tested the product using SCSI to connect to a Windows NT server. The unit supports all Unix and Windows flavours, as well as major backup software packages from companies such as Legato Systems, Computer Associates International, BakBone Software and Veritas Software.
After installing the product, the next step is to configure the settings. You can do that using either the unit's control panel or its administrative GUI, known as SAM (streaming appliance manager).
For the first test, we set the unit to automatically create a second copy for each backup. From the SAM, we set the unit to perform mirroring on two tapes. The front panel of the unit showed the new configuration immediately.
We used BakBone's NetVault
6 software, which displayed our StreamIT unit as a single tape device. But when we launched our backup, the unit began to create two copies simultaneously, just as the vendor promised.
Reinforce weak spots
Automatically creating multiple copies can simplify the life of a data administrator. But if you want to squeeze top performance from your tapes, you should consider setting the unit to 4+1 striping mode, a configuration that writes in parallel on four tapes and uses the fifth tape for recovery.
In this way, StreamIT can make tape backups more resistant to damaging threats such as operational errors or exposure to magnetic fields. Obviously, when a single piece of media is damaged, the entire backup set is also gone. In turn, that creates a strong incentive to run a dual backup with an additional set of tapes. But doing so means more work for your backup system, which can decrease performance.
When configured to work in 4+1 striping mode, StreamIT uses the fifth tape drive to automatically store parity information to rebuild damaged media, thereby making your backup set more resilient without forcing you to spend time creating an extra copy.
The Ultera smart controller makes your tape configuration transparent to your backup software and to the operating system of your servers. StreamIT appears as a single tape unit, letting you focus your configuration efforts on the tape unit itself; the backup software and server OS do not need to be notified.
Even better, if your business needs even more backup - for example, an extra set of tapes to be stored off premises for disaster recovery - StreamIT can also make offline copies of your data.
The 4+1 striping mode worked flawlessly in our tests. And our backups completed significantly faster than they would have using traditional methods. How much faster yours will complete will depend greatly on your server.
The unit's GUI includes a benchmark to predict the best-case scenario performance on your machine. In our case, we discovered that our server fell short of exploiting the nominal performance capacity of 48MBps. It is comforting to know that your tape drive is no longer the weakest link in the chain.
Assuming your server can send data fast enough, StreamIT can finish backup jobs in a fraction of the time taken by traditional tape devices. If your servers are not up to speed, you might have to invest more than the price of the StreamIT unit to unleash its full performance.
But considering that quicker backups mean you can keep your business open longer, and that added reliability easily outweighs the costs of a faster server, it is an investment well-worth making.
The bottom line - Stream IT ****
Business Case: By dramatically reducing the time needed for database backups, this tape device keeps your company open for business and the registers ringing. The product's fifth drive automatically stores information to rebuild any possibly damaged tapes, thereby eliminating the hassles of creating extra copies.
Technology Case: StreamIT is easy to configure and conveniently connects to your servers via either an 80MBps SCSI connection or a fibre link channel. Although it requires a fast server to deliver top performance, StreamIT's reliability and speediness will well reward the investment.
- Speedy and more reliable backups.
- Convenient SCSI and Fibre Channel connectivity.
- Easy scalability using multiple arrays.
- Centralised management GUI.
- Available only for Sony AIT-2 tapes.
- Performance gain limited by server.
Platforms: Windows 95/98/2000, Windows NT, Unix.
Price: Ultra-2 SCSI interface $70,686 (GST incl); Fibre Channel $US82,455 (GST incl).
Maxoptix s StreamIT will be shipping to Australia in May 2001 and will be available through distributor Optisor Australia.
Optisor: 1300 65 72 74