JD750 Loc: SoCal

You should ask him?

The USB Flash drives are actually pretty robust against static discharge and external magnetic fields. They do occasionally get scrambled if one forgets to unmount them. This is a rare event and remembering to unmount them will prevent it. USB Flash drives are small and cheap and it’s easy to keep multiple redundant copies.

And read/write DVDs degrade over time. They are much less reliable in the long run than spinning rust hard drives or even SSDs or thumb drives.

The most reliable way to preserve digital data, is to create multiple copies on good quality separate physical storage elements in different physical locations. You can also store data in the cloud as one of those elements. And it’s bet to leap frog that data to newer units and newer technology, as time passes. FYI - You should be doing that if you have data on DVDs. Optical drives are yesterdays technology. Many new computers don’t even have them.

Joexx

Yes the parity is spread among drives. I was describing the logical allocation of the data storage, not the physical. Data and parity bits are not just on one drive. Raid 5 uses "disk striping". That means that for each "stripe" data is on all but one physical disk. The remaining disk has parity information. The next stripe alters that location of the parity information. This means that logically not physically, a full disk is taken up by the parity information.
The reason that you are seeing 43 TB and NOT 50 TB (5x10) is because a 10 TB disk does not give you 10 TB of data storage. Storage will be decreased depending on how the disk is formatted. Directory and other information (not counted in available data storage calcs) will also take up measurable space.

Joexx

Yes, exactly. The term "Professional" indicates nothing about competency. I am not sure why people on this site find it necessary to insult people, rather than just try and assist and answer a reasonable question.
https://www.google.com/search?client=firefox-b-1-d&q=professional+definition

Klickitatdave Loc: Seattle Washington

From my personal experience CD/DVDs are not remotely reliable over the long term. I even purchased a Blu-Ray burner because of the theoretical 25gb storage capacity but found that Blu-Ray disks are easily damaged and become unreadable. Heaven forbid that you get a fingerprint on any of the disks because it can quickly lead to an unrecoverable erosion of the medium. In any event, I currently use external USB hard drives, Network Assisted Storage (NAS), and IDrive as the final link in my backup plan. BTW, having a NAS allows me to access my files anywhere where there is internet access. Just don't try to transfer multiple gigabytes of data because it will take a really long time to finish. As far as external USB drives I personally avoid mechanical drives and instead use ssds. They are less likely to get damaged if you accidently drop them and allow for much faster data transfers.

JD750 Loc: SoCal

Right. It is a known problem with read write optical storage.

Here is an interesting article comparing SSD TO HDD for data storage:
https://www.backblaze.com/blog/ssd-vs-hdd-future-of-storage/

cjc2 Loc: Hellertown PA

6x10 not 5x10 my friend. That yields @43TB under RAID5, with each drive @ 9.1 TB after formatting. This explanation of RAID 5 is much more accurate. Best of luck.