Troubleshooting a gmirror disk marked broken

Charles Swiger cswiger at
Thu Jun 27 16:16:58 UTC 2013


On Jun 26, 2013, at 7:38 PM, Nikola Pavlović <nzp at> wrote:
[ ... ]
> At the moment I'm attaching smartctl -a results for both disks (ad4 was
> marked broken).  As I'm completely useless in deciphering smartctl
> results (apart from being thought by experience to pretty much
> ignore(tm) the 'Pre-fail' statuses), I'd appreciate assessment from more
> knowledgeable people.

As Adam said, your drives haven't failed, but they are on the way out.
Pay close attention to Reallocated_Sector_Ct, especially if it starts
jumping upwards.

You might also want to check the thermals; the Seagate is running at 52C,
which is significantly hotter than it ought to be, except for maybe a laptop.
I'd much rather see a drive running below 40C....

If you haven't rebuilt the mirror already, running a full disk read scan
against both drives (ie, via "dd if=/dev/ad4 of=/dev/null bs=1m" or similar)
might be prudent.  That will help identify/migrate any sectors which are
failing but still recoverable via ECC to the spare sectors.


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