[CentOS] rescheduling sector linux raid ?

> end_request: I/O error, dev sda, sector 451792231

You should run: smartctl -a /dev/sda

Look for something like this line:

Reallocated_Sector_Ct   0x0033 100  100 036 Pre-fail  Always - 0

If that last value is greater than 0, replace the drive...