Thanks for the info, I am using MDraid. There are no "mddevice" messages
in /var/log/messages and smartctl -a lists no errors on any of the
disks. The disks are about 3 years old, I change them in servers between
3 and 4 years old.
When I was managing systems in a group doing data-intensive processing, I
replaced drives at failure or "end-of-warranty", whichever came first. Over time,
failure rates decreased, but more drives failed shortly after end-of-warranty
(when I wasn't able to get replacements on schedule due to budgets or
supply chain issues). Current disk drive manufacturing seems to be dialed in
to warranty periods, but there will always be some early failures.
I was usually able to get a warranty return authorization on the basis of the
smartctrl report for the failed drive.
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