6/18/2023 0 Comments Disk to disk archiveIf I were big on blind faith, I’d just say opt for online storage and be done with it. If you’re worried about optical drives disappearing, know that optical retains a very strong presence in the archival community, as well as the enterprise, so that should give you some reassurance.Īdvice: Despite its slow speed, optical is pretty perfect for archiving your most important data. The downside is a relatively slow 21MBps writing at best-substantially slower than USB 3.0 hard drives and SSDs. Note that this is all theoretical, but the testing MOs were rigorous and performed by the government of France (BD-R), and the Navy for the Department of Defense (M-Disc DVD).Īvailable in 25GB, 50GB, and 100GB (currently very expensive) flavors, BD-R also has enough capacity to handle long-term backup and archival chores. Only its polycarbonate outer layers reduce that to a mere 1,000 years. Milleniatta’s M-Disc BD-R and DVD+R write-once discs use an even more stable data layer that is rated for 10,000 years. Write-once BD-R HTL (High To Low) can last for 100 to 150 years given a relatively mild environment-i.e., not on your dashboard in Phoenix. However, there are optical discs that are unquestionably the hardiest, handiest archival media available to consumers. Figure 10 years as a best case scenario, but don’t rely on it. The technology is also relatively new, so no one is quite sure how long an SSD will retain data when stored unpowered, but you won’t find companies touting them for long-term backup. The cells, which are electron traps, leak over time. Samsung’s Portable SSD T1 is super fast-up to 350MBps faster than USB 3.0-but most NAND-based storage is only good for about a decade or so.Įxternal SSDs are rugged and virtually shock-proof, but the NAND they use won’t hold data forever. Write-protect them (see the “Methodology” section) before storing them, and rewrite the data every couple of years. You can do everything right with your drive, but drop it on a hard floor as you pull it out of the safety deposit box, and like that, you’re off to the recovery service.Īdvice: If you use hard drives for archiving, use them in pairs or trios-each containing a copy of the same data. A hard drive is also a mechanical device that’s vulnerable to shocks. Consumers can do this with free software called DiskFresh.Įnvironment is also key: Heat, vibration, humidity, and magnetic fields (strong ones are used to erase hard drives) can dramatically shorten operational or shelf life. It figures a loss of magnetic strength/signal at anywhere from 1 percent per year, to 1 percent per decade.įor non-operational drives, it’s industry practice to refresh, i.e., rewrite the data every two or three years. That decade or two longevity figure is based on published figures for coercivity and residual magnetism for current GMR (Giant MagnetoResistance) and SMR (Shingled MagnetoResistance) recording techniques, as well as the latest platter coatings. For the long term, hard drives on the shelf are workable, but require periodic maintenance-so they are not ideal. In constant use, mechanical stresses shorten a drive’s lifespan to three to five years. Fast compared to tape and optical, hard drives are generally reliable for the short term, and if removed from operation and safely stored, may last a decade or two before magnetic properties diminish to the point of producing unrecoverable errors. Portable hard drives are easy to use, faster than optical, but may need their data refreshed every few years.īy far the most common backup media employed by consumers is the external hard drive.
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