One of our regular sends us a question:
How can I test if my hard disk is going bad? I see few errors in /var/log/messages file.
I/O errors in /var/log/messages indicates that something is wrong with the hard disk and it may be failing.
You can check hard disk errors using smartctl command, which is control and monitor utility for SMART disks under Linux / UNIX like operating systems.
smartctl controls the Self-Monitoring, Analysis and Reporting Technology (SMART) system built into many ATA-3 and later ATA, IDE and SCSI-3 hard drives. The purpose of SMART is to monitor the reliability of the hard drive and predict drive failures, and to carry out different types of drive self-tests.
smartctl is a command line utility designed to perform SMART tasks such as printing the SMART self-test and error logs, enabling and disabling SMART automatic testing, and initiating device self-tests.
Make sure S.M.A.R.T. support is enabled in the BIOS.
Next run following command to see if your hard disks support S.M.A.R.T technology:
# smartctl -i /dev/sdb
Now enable SMART:
# smartctl -s on -d ata /dev/sdb
Output:
smartctl version 5.33 [x86_64-redhat-linux-gnu] Copyright (C) 2002-4 Bruce Allen Home page is http://smartmontools.sourceforge.net/ === START OF ENABLE/DISABLE COMMANDS SECTION === SMART Enabled.
Now run overall-health self-assessment test:
# smartctl -d ata -H /dev/sdb
Output:
smartctl version 5.33 [x86_64-redhat-linux-gnu] Copyright (C) 2002-4 Bruce Allen Home page is http://smartmontools.sourceforge.net/ === START OF READ SMART DATA SECTION === SMART overall-health self-assessment test result: PASSED
A sample output from failing hard disk:
smartctl version 5.38 [i686-pc-linux-gnu] Copyright (C) 2002-8 Bruce Allen
Home page is http://smartmontools.sourceforge.net/
=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED
Please note the following marginal Attributes:
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE
190 Airflow_Temperature_Cel 0x0022 044 033 045 Old_age Always FAILING_NOW 56 (96 110 58 25)
The following will provide even more information about failing hard disk:
# smartctl --attributes --log=selftest /dev/sda
Sample outputs:
smartctl version 5.38 [i686-pc-linux-gnu] Copyright (C) 2002-8 Bruce Allen
Home page is http://smartmontools.sourceforge.net/
=== START OF READ SMART DATA SECTION ===
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 098 092 006 Pre-fail Always - 238320363
3 Spin_Up_Time 0x0003 100 100 000 Pre-fail Always - 0
4 Start_Stop_Count 0x0032 100 100 020 Old_age Always - 587
5 Reallocated_Sector_Ct 0x0033 100 100 036 Pre-fail Always - 9
7 Seek_Error_Rate 0x000f 077 060 030 Pre-fail Always - 51672328
9 Power_On_Hours 0x0032 095 095 000 Old_age Always - 4805
10 Spin_Retry_Count 0x0013 100 100 097 Pre-fail Always - 0
12 Power_Cycle_Count 0x0032 100 100 020 Old_age Always - 586
184 Unknown_Attribute 0x0032 100 100 099 Old_age Always - 0
187 Reported_Uncorrect 0x0032 001 001 000 Old_age Always - 417
188 Unknown_Attribute 0x0032 100 099 000 Old_age Always - 4295032833
189 High_Fly_Writes 0x003a 094 094 000 Old_age Always - 6
190 Airflow_Temperature_Cel 0x0022 044 033 045 Old_age Always FAILING_NOW 56 (96 122 58 25)
194 Temperature_Celsius 0x0022 056 067 000 Old_age Always - 56 (0 23 0 0)
195 Hardware_ECC_Recovered 0x001a 043 026 000 Old_age Always - 238320363
197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 49
198 Offline_Uncorrectable 0x0010 100 100 000 Old_age Offline - 49
199 UDMA_CRC_Error_Count 0x003e 200 200 000 Old_age Always - 0
240 Head_Flying_Hours 0x0000 100 253 000 Old_age Offline - 172082159686339
241 Unknown_Attribute 0x0000 100 253 000 Old_age Offline - 2155546016
242 Unknown_Attribute 0x0000 100 253 000 Old_age Offline - 3048586928
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 90% 4789 1746972641
You can read more data from hard disk by typing following command:
# smartctl -d ata -a /dev/sdb
Output:
smartctl version 5.33 [x86_64-redhat-linux-gnu] Copyright (C) 2002-4 Bruce Allen Home page is http://smartmontools.sourceforge.net/ === START OF INFORMATION SECTION === Device Model: WDC WD2500YS-01SHB0 Serial Number: WD-WCANY1729333 Firmware Version: 20.06C03 User Capacity: 251,000,193,024 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: Wed Jul 4 15:04:38 2007 CDT 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: (7800) seconds. Offline data collection capabilities: (0x7b) SMART execute Offline immediate. Auto Offline data collection on/off support. Suspend Offline collection upon new command. Offline surface scan supported. Self-test supported. 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: ( 2) minutes. Extended self-test routine recommended polling time: ( 92) minutes. Conveyance self-test routine recommended polling time: ( 6) minutes. 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 1 Raw_Read_Error_Rate 0x000f 200 200 051 Pre-fail Always - 0 3 Spin_Up_Time 0x0003 190 187 021 Pre-fail Always - 5500 4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 24 5 Reallocated_Sector_Ct 0x0033 200 200 140 Pre-fail Always - 0 7 Seek_Error_Rate 0x000f 200 200 051 Pre-fail Always - 0 9 Power_On_Hours 0x0032 092 092 000 Old_age Always - 6382 10 Spin_Retry_Count 0x0013 100 253 051 Pre-fail Always - 0 11 Calibration_Retry_Count 0x0013 100 253 051 Pre-fail Always - 0 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 23 194 Temperature_Celsius 0x0022 127 096 000 Old_age Always - 23 196 Reallocated_Event_Count 0x0032 200 200 000 Old_age Always - 0 197 Current_Pending_Sector 0x0012 200 200 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0010 200 200 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x003e 200 200 000 Old_age Always - 0 200 Multi_Zone_Error_Rate 0x0009 200 200 051 Pre-fail Offline - 0 SMART Error Log Version: 1 No Errors Logged SMART Self-test log structure revision number 1 No self-tests have been logged. [To run self-tests, use: smartctl -t] 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.
A note about RAID controller
To look at ATA disks behind 3ware SCSI RAID controllers, use syntax such as:
# smartctl -a -d 3ware,2 /dev/sda
# smartctl -a -d 3ware,0 /dev/twe0
Extended self-test of drive
You need to begin an extended self-test of drive /dev/hdc. You can issue this command on a running system. The results can be seen in the self-test log visible with the '-l selftest' option after it has completed.
# smartctl -d ata -t long /dev/sdb
Sample Failing Hard Disk Detailed Report
# smartctl -a /dev/sda
Sample outputs:
smartctl version 5.38 [i686-pc-linux-gnu] Copyright (C) 2002-8 Bruce Allen
Home page is http://smartmontools.sourceforge.net/
=== START OF INFORMATION SECTION ===
Device Model: ST31500341AS
Serial Number: 9VS0TG4B
Firmware Version: CC1H
User Capacity: 1,500,301,910,016 bytes
Device is: Not in smartctl database [for details use: -P showall]
ATA Version is: 8
ATA Standard is: ATA-8-ACS revision 4
Local Time is: Mon Oct 26 21:16:15 2009 IST
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
See vendor-specific Attribute list for marginal Attributes.
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: ( 617) seconds.
Offline data collection
capabilities: (0x7b) SMART execute Offline immediate.
Auto Offline data collection on/off support.
Suspend Offline collection upon new
command.
Offline surface scan supported.
Self-test supported.
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: ( 255) minutes.
Conveyance self-test routine
recommended polling time: ( 2) minutes.
SCT capabilities: (0x103f) SCT Status supported.
SCT Feature Control supported.
SCT Data Table supported.
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 098 092 006 Pre-fail Always - 238338845
3 Spin_Up_Time 0x0003 100 100 000 Pre-fail Always - 0
4 Start_Stop_Count 0x0032 100 100 020 Old_age Always - 587
5 Reallocated_Sector_Ct 0x0033 100 100 036 Pre-fail Always - 9
7 Seek_Error_Rate 0x000f 077 060 030 Pre-fail Always - 51672525
9 Power_On_Hours 0x0032 095 095 000 Old_age Always - 4806
10 Spin_Retry_Count 0x0013 100 100 097 Pre-fail Always - 0
12 Power_Cycle_Count 0x0032 100 100 020 Old_age Always - 586
184 Unknown_Attribute 0x0032 100 100 099 Old_age Always - 0
187 Reported_Uncorrect 0x0032 001 001 000 Old_age Always - 417
188 Unknown_Attribute 0x0032 100 099 000 Old_age Always - 4295032833
189 High_Fly_Writes 0x003a 094 094 000 Old_age Always - 6
190 Airflow_Temperature_Cel 0x0022 044 033 045 Old_age Always FAILING_NOW 56 (96 126 58 25)
194 Temperature_Celsius 0x0022 056 067 000 Old_age Always - 56 (0 23 0 0)
195 Hardware_ECC_Recovered 0x001a 043 026 000 Old_age Always - 238338845
197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 49
198 Offline_Uncorrectable 0x0010 100 100 000 Old_age Offline - 49
199 UDMA_CRC_Error_Count 0x003e 200 200 000 Old_age Always - 0
240 Head_Flying_Hours 0x0000 100 253 000 Old_age Offline - 107168023974595
241 Unknown_Attribute 0x0000 100 253 000 Old_age Offline - 2155546480
242 Unknown_Attribute 0x0000 100 253 000 Old_age Offline - 3048590512
SMART Error Log Version: 1
ATA Error Count: 416 (device log contains only the most recent five errors)
CR = Command Register [HEX]
FR = Features Register [HEX]
SC = Sector Count Register [HEX]
SN = Sector Number Register [HEX]
CL = Cylinder Low Register [HEX]
CH = Cylinder High Register [HEX]
DH = Device/Head Register [HEX]
DC = Device Command Register [HEX]
ER = Error register [HEX]
ST = Status register [HEX]
Powered_Up_Time is measured from power on, and printed as
DDd+hh:mm:SS.sss where DD=days, hh=hours, mm=minutes,
SS=sec, and sss=millisec. It "wraps" after 49.710 days.
Error 416 occurred at disk power-on lifetime: 4786 hours (199 days + 10 hours)
When the command that caused the error occurred, the device was active or idle.
After command completion occurred, registers were:
ER ST SC SN CL CH DH
-- -- -- -- -- -- --
40 51 00 ff ff ff 0f Error: UNC at LBA = 0x0fffffff = 268435455
Commands leading to the command that caused the error were:
CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name
-- -- -- -- -- -- -- -- ---------------- --------------------
25 00 08 ff ff ff ef 00 00:55:03.917 READ DMA EXT
27 00 00 00 00 00 e0 00 00:55:03.818 READ NATIVE MAX ADDRESS EXT
ec 00 00 00 00 00 a0 00 00:55:03.798 IDENTIFY DEVICE
ef 03 46 00 00 00 a0 00 00:55:03.779 SET FEATURES [Set transfer mode]
27 00 00 00 00 00 e0 00 00:55:03.658 READ NATIVE MAX ADDRESS EXT
Error 415 occurred at disk power-on lifetime: 4786 hours (199 days + 10 hours)
When the command that caused the error occurred, the device was active or idle.
After command completion occurred, registers were:
ER ST SC SN CL CH DH
-- -- -- -- -- -- --
40 51 00 ff ff ff 0f Error: UNC at LBA = 0x0fffffff = 268435455
Commands leading to the command that caused the error were:
CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name
-- -- -- -- -- -- -- -- ---------------- --------------------
25 00 08 ff ff ff ef 00 00:55:00.927 READ DMA EXT
27 00 00 00 00 00 e0 00 00:55:00.837 READ NATIVE MAX ADDRESS EXT
ec 00 00 00 00 00 a0 00 00:55:00.817 IDENTIFY DEVICE
ef 03 46 00 00 00 a0 00 00:55:00.800 SET FEATURES [Set transfer mode]
27 00 00 00 00 00 e0 00 00:55:00.747 READ NATIVE MAX ADDRESS EXT
Error 414 occurred at disk power-on lifetime: 4786 hours (199 days + 10 hours)
When the command that caused the error occurred, the device was active or idle.
After command completion occurred, registers were:
ER ST SC SN CL CH DH
-- -- -- -- -- -- --
40 51 00 ff ff ff 0f Error: UNC at LBA = 0x0fffffff = 268435455
Commands leading to the command that caused the error were:
CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name
-- -- -- -- -- -- -- -- ---------------- --------------------
25 00 08 ff ff ff ef 00 00:54:57.903 READ DMA EXT
27 00 00 00 00 00 e0 00 00:54:57.807 READ NATIVE MAX ADDRESS EXT
ec 00 00 00 00 00 a0 00 00:54:57.787 IDENTIFY DEVICE
ef 03 46 00 00 00 a0 00 00:54:57.757 SET FEATURES [Set transfer mode]
27 00 00 00 00 00 e0 00 00:54:57.637 READ NATIVE MAX ADDRESS EXT
Error 413 occurred at disk power-on lifetime: 4786 hours (199 days + 10 hours)
When the command that caused the error occurred, the device was active or idle.
After command completion occurred, registers were:
ER ST SC SN CL CH DH
-- -- -- -- -- -- --
40 51 00 ff ff ff 0f Error: UNC at LBA = 0x0fffffff = 268435455
Commands leading to the command that caused the error were:
CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name
-- -- -- -- -- -- -- -- ---------------- --------------------
25 00 08 ff ff ff ef 00 00:54:54.862 READ DMA EXT
27 00 00 00 00 00 e0 00 00:54:54.767 READ NATIVE MAX ADDRESS EXT
ec 00 00 00 00 00 a0 00 00:54:54.746 IDENTIFY DEVICE
ef 03 46 00 00 00 a0 00 00:54:54.728 SET FEATURES [Set transfer mode]
27 00 00 00 00 00 e0 00 00:54:54.677 READ NATIVE MAX ADDRESS EXT
Error 412 occurred at disk power-on lifetime: 4786 hours (199 days + 10 hours)
When the command that caused the error occurred, the device was active or idle.
After command completion occurred, registers were:
ER ST SC SN CL CH DH
-- -- -- -- -- -- --
40 51 00 ff ff ff 0f Error: UNC at LBA = 0x0fffffff = 268435455
Commands leading to the command that caused the error were:
CR FR SC SN CL CH DH DC Powered_Up_Time Command/Feature_Name
-- -- -- -- -- -- -- -- ---------------- --------------------
25 00 08 ff ff ff ef 00 00:54:51.838 READ DMA EXT
27 00 00 00 00 00 e0 00 00:54:51.736 READ NATIVE MAX ADDRESS EXT
ec 00 00 00 00 00 a0 00 00:54:51.716 IDENTIFY DEVICE
ef 03 46 00 00 00 a0 00 00:54:51.685 SET FEATURES [Set transfer mode]
27 00 00 00 00 00 e0 00 00:54:51.566 READ NATIVE MAX ADDRESS EXT
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 90% 4789 1746972641
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.
Restore From Backup
If any one of these test reports error, replace hard disk and restore data from backup.