EMC has doubled the capacity and throughput of its mainframe virtual tape library (VTL) but it still lags behind IBM. It does exceed Sun's VTL capacity, though.

The EMC DLm (Disk Library for mainframes) now supports up to 1.2PB of raw and usable capacity. EMC says that's almost 3PB compressed capacity, and 1.2GB/sec throughput, by using up to six so-called virtualisation engines. A fully configured DLm needs 13 cabinets.

EMC has improved the DLm's software by adding enhanced administrator support with Secure Remote Services. EMC's Customer Service can directly connect to a customer’s DLm system through a secure IP connection for faster support. Customers can also send off log files, alerts and activities to the EMC support centre for quicker problem resolution. That seems pretty basic, and also pretty necessary. What happened before? Did an EMC support person have to visit the customer's data centre to get this stuff?

EMC says the latest version of DLm software tracks the status of every tape volume in the system and makes that information available within each system. These logs can be replicated to off-site DLm systems, enabling customers to know which tape volumes are usable for their disaster recovery procedures. EMC claims that: "This feature is unique to the industry, providing a key competitive advantage over other mainframe virtual tape libraries."

There's better reporting too. The new DLm is available immediately but no pricing information was released.

There's no deduplication on these boxes, by the way. Where they are used in a disk-to-disk-to-tape environment that's not surprising. EMC is positioning the DLm as a tape replacement device though, and it also has a dedupe-everywhere strategy. That dedupe tide hasn't washed up onto its mainframe VTL shore yet.

Mainframe VTL competitor Shoden has a deduplicating mainframe VTL. It uses a Data Domain dedupe engine writing to HDS drive arrays.

Maybe EMC's DLm needs a Data Domain push? ®

Related stories

• EMC quadruples investments in India (9 September 2009)
• EMC dishes what it will do with Data Domain (20 July 2009)
• Data Domain doubles up dedupe speed (20 July 2009)
• Bus-Tech downsizes VTL for small mainframes (17 July 2009)
• Storage vendors unroll better VTL options (21 May 2009)
• Shoden takes lego approach to de-duped mainframe VTL (14 November 2008)
• EMC does VTL on mainframe, bumps RecoverPoint to 3.0 (25 February 2008)
• Fujitsu Siemens challenges EMC and NetApp on virtual tape (27 November 2006)
• IBM makes tape disappear with virtual storage magic (12 October 2005)