On 18.03.2019 18:30, [email protected] wrote: > Is anyone (reading this list) using USB Flash / Pendrives or [micro]SD cards > for backup? > > I've thought about doing that, especially as they continue to come down in > price, but my experience with them at least in some cases has not been good. > > The worst case seems to be dash cams where, after about a year or so they > just > stop working, but I've had at least one similar case using them for data > storage. > I would never consider these mediums to hold any important backups. There are some reasons why they are cheap. Mainly because they utilize cheap to produce NAND chips with extremely low endurance ratios, like TLC or QLC. But the main problem is, unlike SSDs, USB Flash Drives use controllers without any kind of wear-leveling/wear-controlling and over-provisioning technologies, that ensure the data gets evenly written across all NAND cell blocks and prolong lifespan of every NAND cell block in controllable fashion. USB Flash drives write data anywhere as they see fit, so some NAND cell blocks get more wear than others and could potentially fail at any time, rendering filesystem unusable and making files partially corrupted or lost.
-- With kindest regards, Alexander. ⢀⣴⠾⠻⢶⣦⠀ ⣾⠁⢠⠒⠀⣿⡁ Debian - The universal operating system ⢿⡄⠘⠷⠚⠋⠀ https://www.debian.org ⠈⠳⣄⠀⠀⠀⠀
