Organizations choose to archive data that continues to have value even if it is accessed less frequently. One definition of an archive is a storage platform that secures data without backup. This is achieved by copying, replicating or mirroring data and preventing (if required) the deletion or overwriting of data previously stored, for a specified period or permanently.
Every type of storage technology can and will fail at some time, so planning for that eventuality is crucial. QStar recommends the 3-2-1 Archiving and Data Protection Best Practice to secure data, storing a maximum of three copies, preferably on two different technologies, with one copy of the data offsite for DR purposes. This process provides a way to recover from a media failure.
Hard drives do not typically degrade, they fail, therefore object storage and cloud storage use a similar approach to 3-2-1; securing data through multiple copies but constantly monitoring data. In the event of a media failure, an automated copy is started from known good media to spare media.
Tape drives in libraries also fail, but that does not cause a loss of data. Tape media does degrade over time. However, storing tape cartridges at the correct temperature and humidity means that data stored on tape should last for decades. Data on tape can be verified periodically as verification products and tools have been available for a long-time. What is generally missing is the ability to automatically take remedial action, making additional copies BEFORE the media fails.
QStar has partnered with Hewlett Packard and can now verify and, if needed, copy LTO cartridges in a HP tape library at the first sign of degradation. HP added an API to StoreEver Data Verification, part of their Command View TL software. QStar Archive Manager v6.1 is the first ISV software to support this new API. A verification schedule is created, periodically scanning media in one of three methods; a fast scan taking a few minutes, a medium scan taking around and hour and a full scan taking around five hours. Should a cartridge start to degenerate it can be monitored more frequently or scheduled to be copied during off-peak times. Poor media should not be re-used and is removed from the library.
Data verification options are available with Hewlett Packard’s ESL G3 and MSL6480 tape libraries. However, as other tape library manufacturers add similar API commands to their tape verification software, QStar will support those libraries as well.