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Capacity optimization. As organizations back up more workloads to disk and retain data on disk for longer periods of time, capacity optimization capabilities such as compression and data deduplication become more critical. Gen2 VTLs will need to have these features packaged in a way that addresses functional requirements. That includes deduplicating data across multiple VTL heads, turning deduplication off depending on the workload, and deduplicating data in real-time (inline processing) or batch mode (post-processing) to address performance concerns.
Central management. Organizations that have implemented multiple VTLs (due to scale limitations or by design) created an unexpected management issue: VTL sprawl. Central management of policies and a consolidated view of multiple VTLs can alleviate the management burden, and are important features in the next phase of VTL products.
DR. Another burden of adopting a D2D strategy is safeguarding data in the event of a local outage or disaster. Best practices call for a copy of backup media to be stored offsite. Those first VTL vendors either implemented a "tape export" command to generate a physical duplicate of a virtual tape or directly managed the physical tape library to create duplicate media outside of the backup
| window. Neither approach satisfied the requirement that the backup app maintain full knowledge and control of duplicates. The alternative was to initiate a virtual-to-physical tape copy through the backup app, which meant the backup application was burdened with additional processing and the data was dragged over the network unnecessarily. Gen2 VTLs are leveraging more efficient methods for creating physical media for offsite storage. Taking advantage of backup vendors' APIs, such as Symantec Veritas NetBackup's OpenStorage programming interface, allows VTLs to initiate duplication to tape or a secondary location, while ensuring that the media catalog is synchronized. DR preparedness is also being addressed via local-to-remote VTL-to-VTL replication. Gen2 VTLs take this basic feature a step further by allowing users the flexibility to decide which workloads require site-to-site replication; supporting multiple replication topologies, such as 1:1, and many-to-one ratios; as well as supporting bi-directional replication.
iSCSI support. Improvements in iSCSI performance, wider deployment of 10Gb Ethernet networks and increased support for iSCSI from storage vendors may drive more demand for Ethernet interface support. Users who want to leverage an IP SAN instead of, or in addition to, FC will look for VTLs that support iSCSI connectivity.
We know that organizations of all sizes are under pressure to have secondary data available and quickly accessible in downtime situations. Not doing so can be costly--if not devastating--to organizations. VTLs have emerged as a means to this end for a segment of the market. VTL vendors are responding to these challenges as evidenced by the excitement around their incorporation of data deduplication features. For users, it means scouting out vendors that are improving on these capabilities so you can be prepared to take advantage of the benefits being offered by the next generation of VTL products.
This was first published in September 2008