Why are bad disk sectors numbered strangely, and what happens to them?
Andreas Jellinghaus replied to me with useful advice. But he didn't really answer my questions. Please, if anyone knows the answers to my questions, please kindly say.
(Why the sectors were numbered so strangely,
what does Linux do with them after detecting them,
and how to know if the errors occured during writes or during reads.)
Anyway,
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try the smartmontools package, it has "smartctl" that will show you the discs S.M.A.R.T. details
Good idea, thank you.
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doing a backup couldn't hurt.
It's essentially my crash box at the moment. But I didn't expect visible errors on a 2-year-old disk. (Of course the magnetic layer always has errors but I didn't expect things to get beyond the firmware's automatic assignment and writing of replacement sectors.)
And my reason for posting is that the error logs didn't look the way I would have expected, regarding the sector numbers and the repetitions.
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btw: are you sure cables are ok?
1. There are none.
2. If the connector on the motherboard were coming loose from the motherboard, or if the motherboard had a crack causing intermittent failures in some of its connections, surely the I/O errors would be far more numerous and far more random than the strange occurences I observed.