bad sector in gmirror HDD

Dan Langille dan at
Sat Aug 20 18:16:00 UTC 2011

On Aug 20, 2011, at 1:54 PM, Alex Samorukov wrote:

>> [root at bast:~] # dd of=/dev/null if=/dev/ad2 bs=1m conv=noerror
>> dd: /dev/ad2: Input/output error
>> 2717+0 records in
>> 2717+0 records out
>> 2848980992 bytes transferred in 127.128503 secs (22410246 bytes/sec)
>> dd: /dev/ad2: Input/output error
>> 38170+1 records in
>> 38170+1 records out
>> 40025063424 bytes transferred in 1544.671423 secs (25911701 bytes/sec)
>> [root at bast:~] #
>> That seems to indicate two problems.  Are those the values I should be using
>> with dd?

> You can run long self-test in smartmontools (-t long). Then you can get failed sector number from the smartmontools (-l selftest) and then you can use DD to write zero to the specific sector.

Already done:

Search for 786767

Or did you mean something else?

That doesn't seem to map to a particular sector though... I ran it for a while...

# time dd of=/dev/null if=/dev/ad2 bs=512 iseek=786767 
^C4301949+0 records in
4301949+0 records out
2202597888 bytes transferred in 780.245828 secs (2822954 bytes/sec)

real	13m0.256s
user	0m22.087s
sys	3m24.215s

> Also i am highly recommending to setup smartd as daemon and to monitor number of relocated sectors. If they will grow again - then it is a good time to utilize this disk.

It is running, but with nothing custom in the .conf file.

Dan Langille -

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