JorgeB

Get the syslog once it's stuck to se which filesystem is the problem: cp /var/log/syslog /boot/syslog.txt

It's still cracked, old versions don't turn free once a new one comes out.

Look for spaceinvader1 videos on youtube.

Not sure what you mean, one license is good for any version, but for one server only, and you are using a cracked license.

It will depend on the amount and type of data. https://arstechnica.com/information-technology/2020/06/lawsuit-vs-western-digital-wants-to-end-any-use-of-smr-in-nas-drives/

They can be. There's no way to speed up SMR disks, they are just slower for most write operations, sometimes many times slower then the same thing on CMR.

Unraid can only format array or pool derives, and only after the array is started, format button is next to the array stop button.

Your are using a cracked key: https://unraid.net/buy-genuine-license

The global settings should also work, but if for some reason they are not, use those.

Not directly, depends on how the pool is configured, for a example a single device will be slower than a raid0 pool, but perform about the same as a raid1 pool. Yes, if you consider a mirror a backup.

Depends on how they are assinged, if they are in the same pool it can also be a mirror. What do you mean affect? If you mean if it can be added later, it can. No, You cannot have parity without array data devices. Yes, but not automatically, you could use a script for example, there are also some containers that work for that, look in Apps.

Those are set in /boot/config/disk.cfg, check if they are correct there, they are set disk by disk, for disk1 for example it's these lines: diskWarning.1="50" diskCritical.1="" Disk2 would be: diskWarning.2="50" diskCritical.2="" etc

See if it works correctly now, re-apply for all other disks and check they were added to the smart-one.cfg, you can open the file with any text editor

Run a correcting scrub in the pool, and make sure all errors are corrected.

/boot/config