We've just had a RAID drive go offline. There were no log entries indicating failure prior to 'Mechanical positioning error' - six 'Peripheral device write fault' entries were logged after, and before the controller took it offline and started to rebuild with the hot spare.
There seems very little information about this particular error, apart from a couple of conflicting articles from Sun (this is not a Sun server) one indicates it's just a transient error, another that it can bring the entire controller down.
My interpretation would be that the drive head seized and the drive is toast - and if the RAID controller recognised it and took it offline then I am lucky. Would this be a reasonable assessment?
The failed drive was one that was replaced in 2018, one of many (11 to date) Seagate drives that have failed on this array.