Every time I run a parity check I get about 10-15 errors just like the one below.

Sep  7 20:58:13 tower kernel: ata4.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
Sep  7 20:58:13 tower kernel: ata4.00: irq_stat 0x40000001
Sep  7 20:58:13 tower kernel: ata4.00: failed command: READ DMA EXT
Sep  7 20:58:13 tower kernel: ata4.00: cmd 25/00:c0:b7:bb:9e/00:02:38:00:00/e0 tag 0 dma 360448 in
Sep  7 20:58:13 tower kernel:          res 51/40:2f:38:bc:9e/00:02:38:00:00/e0 Emask 0x9 (media error)
Sep  7 20:58:13 tower kernel: ata4.00: status: { DRDY ERR }
Sep  7 20:58:13 tower kernel: ata4.00: error: { UNC }
Sep  7 20:58:13 tower kernel: ata4.00: configured for UDMA/133
Sep  7 20:58:13 tower kernel: ata4: EH complete

 

Interesting parts of the SMART status report for that drive below:

SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
196 Reallocated_Event_Count 0x0032   200   200   000    Old_age   Always       -       0
197 Current_Pending_Sector  0x0032   200   200   000    Old_age   Always       -       18
198 Offline_Uncorrectable   0x0030   200   200   000    Old_age   Offline      -       1

SMART Self-test log structure revision number 1
Num  Test_Description    Status                  Remaining  LifeTime(hours)  LBA_of_first_error
# 1  Extended offline    Completed: read failure       80%      6371         596108986

 

My question is whether this just some failing blocks (which the drive should eventually relocate) or whether I need to replace this drive.

 

Any advice would be appreciated.

syslog-2011-09-08.txt

SMART.txt

I'd replace the drive with a spare and then run pre-clear to see what happens with the sector reallocation.