Centos smartd disk monitoring daemon

smartd is a daemon monitoring that monitor the harddrives.
SMART = Self-Monitoring, Analysis and Reporting Technology
If you have a problem on a harddrive it will be logged in /var/log/messages and reported in daily mail to root
Example

[root@ks ~]# smartctl -a /dev/sda -d ata
smartctl version 5.36 [i686-redhat-linux-gnu] Copyright (C) 2002-6 Bruce Allen
Home page is http://smartmontools.sourceforge.net/

=== START OF INFORMATION SECTION ===
Device Model:     ST3120811AS
Serial Number:    5PT03V7P
Firmware Version: 3.AAE
User Capacity:    120.034.123.776 bytes
Device is:        Not in smartctl database [for details use: -P showall]
ATA Version is:   7
ATA Standard is:  Exact ATA specification draft version not indicated
Local Time is:    Thu Mar 12 15:31:55 2009 CET
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED

General SMART Values:
Offline data collection status:  (0x82) Offline data collection activity
                                        was completed without error.
                                        Auto Offline Data Collection: Enabled.
Self-test execution status:      (   0) The previous self-test routine completed
                                        without error or no self-test has ever
                                        been run.
Total time to complete Offline
data collection:                 ( 430) seconds.
Offline data collection
capabilities:                    (0x5b) SMART execute Offline immediate.
                                        Auto Offline data collection on/off support.
                                        Suspend Offline collection upon new
                                        command.
                                        Offline surface scan supported.
                                        Self-test supported.
                                        No Conveyance Self-test supported.
                                        Selective Self-test supported.
SMART capabilities:            (0x0003) Saves SMART data before entering
                                        power-saving mode.
                                        Supports SMART auto save timer.
Error logging capability:        (0x01) Error logging supported.
                                        General Purpose Logging supported.
Short self-test routine
recommended polling time:        (   1) minutes.
Extended self-test routine
recommended polling time:        (  51) minutes.

SMART Attributes Data Structure revision number: 10
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  1 Raw_Read_Error_Rate     0x000f   116   059   006    Pre-fail  Always       -       110338494
  3 Spin_Up_Time            0x0003   096   095   000    Pre-fail  Always       -       0
  4 Start_Stop_Count        0x0032   100   100   020    Old_age   Always       -       90
  5 Reallocated_Sector_Ct   0x0033   100   100   036    Pre-fail  Always       -       18
  7 Seek_Error_Rate         0x000f   075   060   030    Pre-fail  Always       -       40255908
  9 Power_On_Hours          0x0032   099   099   000    Old_age   Always       -       1249
 10 Spin_Retry_Count        0x0013   100   100   097    Pre-fail  Always       -       0
 12 Power_Cycle_Count       0x0032   100   100   020    Old_age   Always       -       98
187 Unknown_Attribute       0x0032   100   100   000    Old_age   Always       -       0
189 Unknown_Attribute       0x003a   100   100   000    Old_age   Always       -       0
190 Unknown_Attribute       0x0022   053   048   045    Old_age   Always       -       824901679
194 Temperature_Celsius     0x0022   047   052   000    Old_age   Always       -       47 (Lifetime Min/Max 0/20)
195 Hardware_ECC_Recovered  0x001a   067   051   000    Old_age   Always       -       210799346
197 Current_Pending_Sector  0x0012   098   097   000    Old_age   Always       -       48
198 Offline_Uncorrectable   0x0010   098   097   000    Old_age   Offline      -       48
199 UDMA_CRC_Error_Count    0x003e   200   200   000    Old_age   Always       -       0
200 Multi_Zone_Error_Rate   0x0000   100   253   000    Old_age   Offline      -       0
202 TA_Increase_Count       0x0032   100   253   000    Old_age   Always       -       0

SMART Error Log Version: 1
No Errors Logged

SMART Self-test log structure revision number 1

SMART Selective self-test log data structure revision number 1
 SPAN  MIN_LBA  MAX_LBA  CURRENT_TEST_STATUS
    1        0        0  Not_testing
    2        0        0  Not_testing
    3        0        0  Not_testing
    4        0        0  Not_testing
    5        0        0  Not_testing
Selective self-test flags (0x0):
  After scanning selected spans, do NOT read-scan remainder of disk.
If Selective self-test is pending on power-up, resume after 0 minute delay