With the rise of Chia farming, many hard drives provisioned in LowEnd dedicated servers are arriving having suffered phenomenal (ab)use. Sure, your dedi provider is usually on the hook to replace if your drive dies, but who wants to go through that kind of hassle and disruption?
Here’s a quick technique for checking what state your hard drive is. Note that this method works only on dedicated servers where you have true access to your physical hard drive. It does not work on virtual servers, where the storage is virtualized.
Hard drives include an on-board monitoring system called S.M.A.R.T (Self-Monitoring, Analysis and Reporting Technology) which can “detect and report various indicators of drive reliability with the intent of anticipating imminent hardware failures.” Various statistics and data are kept on-board and you can query these to obtain information that will tell you about the drive’s history.
To begin with, install the smart-tools package. For example, on Debian systems:
apt-get install smartmontools
Next, query the drive in question:
smartctl -a /dev/sdg
For example, here is a report of a nearly new (less than 72 hours use) Western Digital 6TB Black SATA drive:
# smartctl -a /dev/sdg smartctl 6.6 2016-05-31 r4324 (x86_64-linux-4.9.0-16-amd64) (local build) Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org === START OF INFORMATION SECTION === Device Model: WDC WD6003FZBX-00K5WB0 Serial Number: V9JGEZSL LU WWN Device Id: 5 000cca 0bde2c0ba Firmware Version: 01.01A01 User Capacity: 6,001,175,126,016 bytes (6.00 TB) Sector Sizes: 512 bytes logical, 4096 bytes physical Rotation Rate: 7200 rpm Form Factor: 3.5 inches Device is: Not in smartctl database (for details use: -P showall) ATA Version is: ACS-2, ATA8-ACS T13/1699-D revision 4 SATA Version is: SATA 3.2, 6.0 Gb/s (current: 6.0 Gb/s) Local Time is: Sun Jul 11 11:52:27 2021 PDT 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: ( 87) 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: ( 2) minutes. Extended self-test routine recommended polling time: ( 593) minutes. SCT capabilities: (0x0035) SCT Status supported. SCT Feature Control supported. SCT Data Table supported. 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 0x000b 100 100 016 Pre-fail Always - 0 2 Throughput_Performance 0x0004 133 133 054 Old_age Offline - 92 3 Spin_Up_Time 0x0007 100 100 024 Pre-fail Always - 0 4 Start_Stop_Count 0x0012 100 100 000 Old_age Always - 1 5 Reallocated_Sector_Ct 0x0033 100 100 005 Pre-fail Always - 0 7 Seek_Error_Rate 0x000a 100 100 067 Old_age Always - 0 8 Seek_Time_Performance 0x0004 128 128 020 Old_age Offline - 18 9 Power_On_Hours 0x0012 100 100 000 Old_age Always - 69 10 Spin_Retry_Count 0x0012 100 100 060 Old_age Always - 0 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 1 192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 4 193 Load_Cycle_Count 0x0012 100 100 000 Old_age Always - 4 194 Temperature_Celsius 0x0002 141 141 000 Old_age Always - 39 (Min/Max 25/41) 196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 0 197 Current_Pending_Sector 0x0022 100 100 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0008 100 100 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x000a 200 200 000 Old_age Always - 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.
Here are some areas in the report to look at:
Power_On_Hours: This will give you the total hours the drive has been powered on. This does not mean necessarily in use, but rather it was spun up and receiving electricity.
Power_Cycle_Count: How often has the drive been power cycled?
Raw_Read_Error_Rate, Seek_Error_Rate, Offline_Uncorrectable: these should ideally be zero.
Reallocated_Event_Count: Ideally this should be zero or a very low number.
SMART overall-health self-assessment test result: not surprisingly, you want this to say PASSED.
If you receive a drive whose age indicates it’s several years old, or has many errors, you may wish to contact your dedi provider and ask for a preventative replacement rather than risk failure.