Am 30.11.20 um 14:11 schrieb antlists:

On 30/11/2020 12:13, Reindl Harald wrote:

quoted

but i fail to see the difference and to understand why reality and 
superblock disagree,

In YOUR case the array was degraded BEFORE shutdown. In the OP's case, 
the array was degraded AFTER shutdown

no, no and no again!

* the array is full opertional
* smartd fires a warning
* the machine is shut down
* after that the drive is replaced
* so the array get degraded AFTER shutdown
* at power-on RAID partitions are missing