News

posted on 07 April 2008 14:52

Sun has introduced its first de-duplicating virtual tape library (VTL) as well as upgrading the capabilities of its two existing VTL products for Widows and Unix/Linux servers.

VTLs backup data to hard drive storage arrays presented as tape drives to backup software applications. This dramatically shortens backup time and speeds restores because there is no need to wait for a tape cartridge to be loaded into a dive and streamed through to arrive at the desired file.

Sun has its VSM mainframe VTL, using Sun's own software, and three open systems VTLs:

- VTL Value based on the X4500 storage-enhanced 'Thumper' server, FalconStor VTL software, ZFS  and 24TB capacity with 500GB serial ATA (SATA) drives;

- VTL Plus based on the SunFire v40z dual Opteron server, OEM'd FalconSor VTL SW and up to 224TB capacity;

- And a de-duping VTL using Diligent ProtecTIER, an X4600 Sun server and StorageTek 6000 drive array. De-duplication dramatically shrinks file sizes by removing block-level data that has already been stored once and replacing it with pointers.

VTL Value

Sun has added 750GB and 1TB drives to the VTL Value, enabling new capacity points of 36 and 48TB.

VTL Plus

It has also revved the VTL PLus by using SunFire X4200 and X4600 servers which doubles backup performance to between 700MB/sec to 2,200MB/sec depending upon the model. There is also better backup application integration with support for NDMP v4.0 enabling , for example, NetBackup 6.5 to use VTL Plus as a proxy for CPU-intensive operations, effectively offloading the host server.

VTL Prime

The VTL Prime is the first VTL from Sun to use its own (OEM'd) de-duplication software. In other words, it's FalconStor's de-dupe technology, which does the de-duplication as a post-process after backup data has been loaded onto the product's disks. Dan Albright, VTL senior product manager at Sun, said: "Post-process versus inline is a religious discussion; angels on a pinhead type stuff."

There are five VTL Prime models. The entry level model has 3TB of usable capacity and costs about $40,000. The first three or R-series models use the SunFire 4200 server with the other two C-series models using the faster 4600 server and Sun's 6140 drive array. The high-end model has a 42TB capacity limit.

The VTL Prime has a throughput of 120MB/sec to 400MB/sec depending upon the model. This is slower than the enhanced VTL PLus which uses the same servers but doesn't de-dupe its data. Sun positions the VTL Prime as a standalone VTL for smaller and/or remote offices, or as a second VTL backup tier behind a VTL Plus.

C-series are central or core VTLs with the R-series being remote office VTLs. Replicating their data to the core systems needs much less bandwidth because the data has been de-duplicated.

Through the NDMP v4 support, NetBackup on a media server can have VTL Plus content moved over to a VTL Prime. There would be a few weeks of backup data stored on the VTL Plus and months of it stored on the VTL Prime, greatly extending the time period over which restores can be carried out at disk speed.

Albright said: "Many customers are trying to linmit their dependence on tape for backup. Tape is for archive." He said that Sun VTLs multi-stream data whereas a tape can only single-stream data; that's the advantage of disk.

^{[Chris Mellor.]}