I am trying to add a new disc to the array and it unmounts after reboot. I did the standard preclear, format, mount, & added it to the array. It temporarily showed the new disc as part of the array, but after a reboot, it drops it back down to the bottom and says "Unmountable: not mounted". 

 

The two things that stand out are the excessive amounts of reads and writes on this disc as well as how it unmounts after showing mounted and part of the array. 

 

 

 

 

Attached are screen shots of the discs as well as the logs. 

 

 

Whats the safe next move? I just want to make sure I dont do anything to lose data. Do I attempted to format unmountable discs and adding to the array again? 

Thanks!

bucktower-syslog-20210120-0949.zip

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I did the standard preclear, format, mount, & added it to the array.

That's not the normal process of adding a new disk to the array. The order of the steps is wrong. You really need to post your diagnostics.

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did the standard preclear, format, mount, & added it to the array

There is nothing "standard" about that sequence.

 

1. Preclear is fine if you want to test the disk. Otherwise you can just add it to the array and let Unraid clear it.
2. Format must be done AFTER adding a disk to the array.
3. Don't know what exactly you mean by "mount". I suspect you are using the word incorrectly.
4. As mentioned, adding the disk to the array must happen before formatting.

 

Will probably copy Have copied the thread here to General Support after examining the diagnostics syslog since this is likely user error instead of a bug.

 

Since you rebooted before getting that syslog nothing to see except the fact that disk13 isn't mounting, probably because it hasn't been formatted.

 

6 minutes ago, trurl said:

Preclear is fine if you want to test the disk. Otherwise you can just add it to the array and let Unraid clear it.

A disk must be clear when adding it to a NEW slot in an array that already has valid parity. This is so parity will remain valid. A clear disk is all zeros and so has no effect on parity.

 

8 minutes ago, trurl said:

Format must be done AFTER adding a disk to the array.

If you format a precleared disk before adding it to the array, it is no longer clear. Format writes an empty filesystem to the disk. So, it is no longer all zeros, and Unraid will have to clear it again.

 

You didn't specifically mention Unraid clearing the disk again after you added it. Perhaps you didn't notice, or perhaps you did something you haven't told us about.

 

 

 

When you format a disk in the array, parity is updated just like any other write operation, and so parity remains in sync.

 

Only clear disks can be added to the array, then any write operation that happens after that updates parity so it remains in sync.

11 minutes ago, trurl said:

You didn't specifically mention Unraid clearing the disk again after you added it. Perhaps you didn't notice, or perhaps you did something you haven't told us about.

This is the main thing I wonder about with regard to giving further advice. If you did something you haven't told us about that prevented Unraid from clearing the disk again, then parity is invalid.