looking at the logs I see several errors. The smart status is PASSED, but even if It is verbose It isn't clear what is going on. Should the disk be replaced?
Attached dmesg and smart logs
# dmesg
ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
ata1.00: BMDMA stat 0x64
ata1.00: failed command: READ DMA EXT
ata1.00: cmd 25/00:08:61:5d:64/00:00:5f:00:00/e0 tag 0 dma 4096 in
res 51/40:00:63:5d:64/40:00:5f:00:00/00 Emask 0x9 (media error)
ata1.00: status: { DRDY ERR }
ata1.00: error: { UNC }
ata1.00: configured for UDMA/133
sd 0:0:0:0: [sda] Unhandled sense code
sd 0:0:0:0: [sda] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
sd 0:0:0:0: [sda] Sense Key : Medium Error [current] [descriptor]
Descriptor sense data with sense descriptors (in hex):
72 03 11 04 00 00 00 0c 00 0a 80 00 00 00 00 00
5f 64 5d 63
sd 0:0:0:0: [sda] Add. Sense: Unrecovered read error - auto reallocate failed
sd 0:0:0:0: [sda] CDB: Read(10): 28 00 5f 64 5d 61 00 00 08 00
ata1: EH complete
# smartctl -x /dev/sda
smartctl 5.40 2010-07-12 r3124 [x86_64-unknown-linux-gnu] (local build)
Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net
=== START OF INFORMATION SECTION ===
Model Family: Seagate Barracuda 7200.12 family
Device Model: ST31000528AS
Serial Number: 9VP8WA3X
Firmware Version: CC38
User Capacity: 1,000,204,886,016 bytes
Device is: In smartctl database [for details use: -P show]
ATA Version is: 8
ATA Standard is: ATA-8-ACS revision 4
Local Time is: Sun Feb 10 16:13:22 2013 CET
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
....
Error 36 [15] occurred at disk power-on lifetime: 16731 hours (697 days + 3 hours)
When the command that caused the error occurred, the device was active or idle.
After command completion occurred, registers were:
ER -- ST COUNT LBA_48 LH LM LL DV DC
-- -- -- == -- == == == -- -- -- -- --
40 -- 51 00 00 00 5f 5d 00 64 63 00 00 Error: UNC at LBA = 0x5f5d006463 = 409582199907
SCT Error Recovery Control:
Read: Disabled
Write: Disabled
SATA Phy Event Counters (GP Log 0x11)
ID Size Value Description
0x000a 2 8 Device-to-host register FISes sent due to a COMRESET
0x0001 2 0 Command failed due to ICRC error
0x0003 2 0 R_ERR response for device-to-host data FIS
0x0004 2 0 R_ERR response for host-to-device data FIS
0x0006 2 0 R_ERR response for device-to-host non-data FIS
0x0007 2 0 R_ERR response for host-to-device non-data FIS