FRAMINGHAM, MASS. - A technology that backs up mainframe data to disk rather than tape to save money and floor space while enhancing data recoverability got a boost recently from start-up Diligent Technologies.\nDiligent is taking a run at virtual tape technology - long characterized by products from IBM and StorageTek - that backs up mainframe data faster and more economically to large tape libraries rather than individual tape drives.\nThe company, which bought technology from\u00a0EMC in September called CopyCross, is expected to introduce software this week, called Diligent Tape Virtualization - Mainframe Systems, that backs up data from IBM zSeries servers running zOS to an EMC Symmetrix, Hitachi Lightning or IBM Enterprise Storage Server.\nTraditionally, mainframe virtual tape systems emulate the processing of tape in zOS environments and save the data to disk or massive tape libraries, as if it were data sets for multiple IBM 3840, MagStar or Storage 9840 tape drives. By using disks or tape libraries, it reduces the floor space consumed by tape, improves the availability of data and lets multiple servers share the data.\n"Users need to have increased flexibility between tape and disk," says Jamie Gruener, an analyst with The Yankee Group. "Virtual tape software lets you take what was targeted for tape and put it on disk. Diligent is taking technology that is focused on the mainframe environment and, long term, extending it to open systems."\nCEO and founder Doron Kempel says Diligent will support arrays attached to Fibre Channel storage-area networks (SAN) in the first half of next year and technology that lets data residing on one storage array be replicated to another remote array for disaster-recovery purposes.\nOne user, who is consolidating his server and storage operations, has experience with both traditional virtual tape technology and with the new open systems approach.\n"Data comes in from the servers, goes onto the IBM Virtual Tape Server and is then pumped later to the individual tape systems," says James Haney, vice president of architecture for appliances maker Whirlpool in Benton Harbor, Mich.\n\n\n\n\n\n\n\n\n\nStorage soup\nVendors have several implementations for creating virtual tape systems, which back up mainframe data to disk, rather than slower, more cumbersome tape.\n\n\n\n\n\n\n\n\n\n\n\nVendor\nProduct name\nFunction\nConnectivity\nConnection type\n\n\nBustech\nMainframe Tape Appliance\nIBM zSeries, zOS to open system disks\nAny NAS, SAN or direct-attached storage\nESCON\n\n\nDiligent Technologies\nDiligent Tape Virtualization\u2013 Mainframe Systems\nIBM zSeries, zOS to attached mainframe disks\nHP, EMC, Hitachi and IBM\nESCON, FICON\n\n\nNeartek\nVirtual Storage Engine2\nMainframe, midrange to open system disks\nHP, EMC, Hitachi and IBM StorageTek\nESCON, FICON, SCSI\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nUsing IBM's tape server has saved Haney space. "We've taken 4,000 tapes off our floor doing it this way. We have so few stand-alone tape racks anymore," he says.\nDiligent is not the first vendor to introduce virtual tape technology. Initially, vendors such as IBM, Computer Associates and StorageTek focused on replacing IBM 3840 tape drives with large tape libraries. As drives became more inexpensive and as the time it took to back up the network expanded, vendors started to look for other methods of backing up data that would give them faster availability and reliably, at a lower cost. EMC's CopyCross software, proved to be an excellent alternative to mainframe tape libraries because, while looking like tape to the host, it wrote data to the Symmetrix as if it was tape.\nAs Fibre Channel SANs were installed and as mainframes were tied into them, the need to back up to a common source grew. Several companies, such as Neartek and Bustech, introduced virtual tape technology that could back up mainframe and open systems data to shared disks. Users adopted it, too.\nAt Whirlpool, Haney has consolidated storage onto six IBM Enterprise Storage Servers, which he shares among an IBM mainframe, midrange and Intel-based servers. Soon, he will start consolidating his virtual tape operations to the disks of the IBM Enterprise Storage Server, where backup will take less time and data will be available more quickly.\nDiligent's software is priced by mainframe processor. A typical system would cost $50,000 to $100,000 per processor. The product is available now.