Question Doubt archival media

[gamerfan]

Below optical media DVD, Bluray For long-term storage of files which media is more reliable and safe, SSD, HDD, USB Flash Drive, MicroSD card?

 

[Jimminy]

A stone tablet and a chisel beats them all.

 

[Velgen]

Any flash based media is not good for archival/cold storage due to the nature of how flash memory functions. It is perfectly reliable provided it is provided power, but otherwise if it's just sitting in a drawer for a few years don't be surprised to find it corrupted when you come back to it. HDDs would be below optical media in my personal experience, but ya SSD, flash drive, and MicroSD/SD are all the same thing at the end of the day FLASH. Can't tell you how many customers kept the only copy of the orders I did for them on a flash drive only for them to come back with it having corrupted after sitting in a drawer for a year or two. The move from SLC to MLC to TLC and finally QLC seems to not only have worsened endurance but also data retention when the flash is not provided power. So I would never recommend any flash based storage for archival/cold storage

 

[gamerfan]

I read that NOR flash is very good at retention

HDDs unfortunately also use flash memory to store Bios/firmware and this memory is located on the PCB of the HDDs this would be a problem if they corrupted the HDD unusable

 

[Velgen]

HDDs unfortunately also use flash memory to store Bios/firmware and this memory is located on the PCB of the HDDs this would be a problem if they corrupted the HDD unusable

Yes that is also an issue, but generally it will be less prone to corruption than your SSDs, flash drives, or SD cards. Honestly nothing consumer grade besides optical media are particularly reliable as archival/cold storage unfortunately, but if I had to order them it would be Optical > HDD > SSD >= Flash Drive = SD Card > MicroSD. Have seen a ridiculous amount of corrupted MicroSDs and I am not sure if that is due to their ubiquity or if they're more prone to corruption. Considering I worked in a camera shop one would think that I would be seeing more SD cards coming in with corruption than MicroSDs. Optical media also has it's own issues, but so does everything it is just what I trust most of what is readily available to consumers.

 

[DavidC1]

Yes that is also an issue, but generally it will be less prone to corruption than your SSDs, flash drives, or SD cards. Honestly nothing consumer grade besides optical media are particularly reliable as archival/cold storage unfortunately, but if I had to order them it would be Optical > HDD > SSD >= Flash Drive = SD Card > MicroSD.

This seems like a reasonable order.

Western Digital had a slide basically summarizing the faster the fundamental media is in terms of access times(us and ns), the retention times get shorter. So DRAM has almost zero retention time(it needs to be refreshed), than Optane was 3-6 months, then you had NAND SSDS that are rated for ~10 years.

USB flash drives are ridiculously cheap per GB so they use really low quality flash everywhere, which doesn't help with retention. So think of highest quality NAND going into Enterprise, then average ones into SSDs, and lowest quality that they would otherwise junk going into USB flash drives.

Optical can be pretty good too, but I heard like many things you have to keep them stored in a cool place away from sunlight because it degrades exponentially faster otherwise.