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On 06-Aug-12 10:50, Kraus Philipp wrote: |
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> I'm using a software raid with mdadm (mirror). A few days ago the |
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> mdadm removes during the boot process one disk and sets the raid |
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> inactive. The disk contains no errors (smartctl) and nothing is |
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> reported in the logs. I reassemble the disk and activate the raid |
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> again. Reboot the system and my disk are in sync and everything works |
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> fine. |
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> |
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> I'm a little bit confused about it. Does anybody has got an idea, why |
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> the array lost a disk? |
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It may happen quite frequently with common (non-raid) drives |
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which do not have TLER implemented. |
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Modern drives have some kind of internal error-recovery |
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procedure which covers remapping of bad/weak sectors. This |
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might take quite long time (a few seconds, or even tens |
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of seconds) and as a result raid-controller (or raid-software) |
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marks drive as failed because it does not respond in |
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given time. |
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Solution is to use "raid-edition" drives, with TLER |
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(time limited error recovery) implemented. On some drives |
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this can be activated by using some utility (i.e. WDTLER.EXE). |
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You can read more about it on the net, i.e.: |
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http://en.wikipedia.org/wiki/Time-Limited_Error_Recovery |
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http://en.wikipedia.org/wiki/RAID#Problems_with_RAID |
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|
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Jarry |
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-- |
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