unreadable (pending) sectors

[Miroslav Lachman]

Hi all,

a few days ago I start reading records like this in /var/log/messages

Feb  3 17:27:22 roxy smartd[71846]: Device: /dev/ad6, 1 Currently 
unreadable (pending) sectors
Feb  3 17:27:22 roxy smartd[71846]: Device: /dev/ad6, 1 Offline 
uncorrectable sectors

ad6 is one of two drives in gmirror, so I am not so "scared" ;)

Related parts of output of smartctl -a /dev/ad6

197 Current_Pending_Sector  0x0012   100   100   000    Old_age   Always 
       -       1
198 Offline_Uncorrectable   0x0030   100   100   000    Old_age 
Offline      -       1
199 UDMA_CRC_Error_Count    0x003e   200   200   000    Old_age   Always 
       -       0
200 Multi_Zone_Error_Rate   0x000a   100   100   000    Old_age   Always 
       -       0
201 Soft_Read_Error_Rate    0x000a   100   100   000    Old_age   Always 
       -       2

# 1  Extended offline    Completed: read failure       10%      4118 
      474119936
# 2  Short offline       Completed without error       00%      4115 
      -

How can I determine which file belongs to LBA 474119936 / How can I try 
to write to this sector, so drive can internaly realocate this bad sector?
Is there any special tools/commands to this?

Miroslav Lachman