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MarkdownHard Drive Introspection
Serge Y. Stroobandt
Copyright 2013–2022, licensed under Creative Commons BY-NC-SA
TODO
- binding text
Introduction
- Not so long ago, I came across a badly configured laptop hard drive. On battery power, it was spinning up and down almost every half minute. This and other instances, lent themselves as a great opportunity to discover the vast array of freely available GNU/Linux hard drive tools.
Listing block devices
$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 298.1G 0 disk
├─sda1 8:1 0 512M 0 part /boot
├─sda2 8:2 0 4.5G 0 part
├─sda3 8:3 0 44G 0 part /
└─sda4 8:4 0 249.1G 0 part /home
sr0 11:0 1 1024M 0 rom
$ lsblk -o NAME,TYPE,SIZE,MODEL,SERIAL,WWN,MOUNTPOINT
NAME TYPE SIZE MODEL SERIAL WWN MOUNTPOINT
nvme0n1 disk 931.5G Samsung SSD 970 EVO 1TB S467NX0MB16745H eui.0025385b91b14537
├─nvme0n1p1 part 232.9G eui.0025385b91b14537 /
└─nvme0n1p2 part 698.6G eui.0025385b91b14537 /homeListing by ID
$ ls -l /dev/disk/by-id
total 0
…
lrwxrwxrwx 1 root root 9 Nov 13 23:04 scsi-SATA_WDC_WD10EARS-00_WD-WCAV56524564 -> ../../sda
lrwxrwxrwx 1 root root 10 Nov 11 10:48 scsi-SATA_WDC_WD10EARS-00_WD-WCAV56524564-part1 -> ../../sda1
lrwxrwxrwx 1 root root 10 Nov 11 10:48 scsi-SATA_WDC_WD10EARS-00_WD-WCAV56524564-part9 -> ../../sda9
…
$ ls -dl --color=always /dev/disk/by-id/* |sed s:^.*/dev:/dev:
…
/dev/disk/by-id/ata-WDC_WD10EADS-00L5B1_WD-WCAU4D512265 -> ../../sda
/dev/disk/by-id/ata-WDC_WD10EADS-00L5B1_WD-WCAU4D512265-part1 -> ../../sda1
/dev/disk/by-id/ata-WDC_WD10EADS-00L5B1_WD-WCAU4D512265-part9 -> ../../sda9
…
/dev/disk/by-id/wwn-0x50014ee1575de8a2 -> ../../sda
/dev/disk/by-id/wwn-0x50014ee1575de8a2-part1 -> ../../sda1
/dev/disk/by-id/wwn-0x50014ee1575de8a2-part9 -> ../../sda9Note that a drive or a drive partition can have more than one by-id. Apart from the ID based on the brand, model name and the serial number, nowadays there might also be a wwn- ID. This is the unique World Wide Name (WWN) and is also printed on the drive case.
Both type of IDs work fine with ZFS, but the WWN is a bit less telling. If these WWN IDs are not referenced by the production system (e.g. a ZFS that has not been exported yet), these may simply be removed with sudo rm wwn-*. Trust me; I have done that. Nothing can go wrong as long as the ZFS is in an exported state before doing this. After all, WWN IDs are mere symbolic links to sd devices that are created at drive detection. They will automatically reappear when the system is rebooted. Internally, Linux always references sd devices.
Listing UUIDs
Universally Unique Identifier (UUID)
$ ls -l /dev/disk/by-uuid
total 0
lrwxrwxrwx 1 root root 10 Sep 1 13:08 438b7a73-11c5-466c-b795-fcf6d0997056 -> ../../sda2
lrwxrwxrwx 1 root root 10 Sep 1 13:08 7c581345-6850-44df-a387-cdf62cb09bba -> ../../sda4
lrwxrwxrwx 1 root root 10 Sep 1 13:08 8ef04775-ec47-4663-bc77-7e6f8980e195 -> ../../sda3
lrwxrwxrwx 1 root root 10 Sep 1 13:08 9b5c2cd5-43de-4a56-9da9-741710d28dc3 -> ../../sda1$ sudo apt install util-linux
$ sudo blkid /dev/sda2
/dev/sda2: UUID="438b7a73-11c5-466c-b795-fcf6d0997056" TYPE="swap" PARTUUID="00035ac0-02"Physical identification
For the physical identification using storage enclosure LEDs, I created the following bash script:
#!/usr/bin/env bash
# https://serverfault.com/a/1108701/175321
if [[ $# -gt 0 ]]
then
while true
do
dd if=$1 of=/dev/null >/dev/null 2>&1 || sudo dd if=$1 of=/dev/null >/dev/null 2>&1
sleep 1
done
else
echo -e '\nThis command requires a /dev argument.\n'
fiUnlike ledctl from the ledmon package, this script also works fine with non-Intel hard drive controllers.
Free disk space
The df command is used to query the amount of free disk space. The -h option is necessary to print the amount of free disk space in a human-readable fashion. Only local file systems are shown with the -l option. To show file system types, use the -T option.
$ df -hlT
Filesystem Type Size Used Avail Use% Mounted on
udev devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs tmpfs 379M 2.5M 376M 1% /run
/dev/sda1 ext4 32G 20G 11G 65% /
tmpfs tmpfs 1.9G 4.0K 1.9G 1% /dev/shm
tmpfs tmpfs 5.0M 4.0K 5.0M 1% /run/lock
tmpfs tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sda2 ext4 79G 18G 58G 24% /home
tmpfs tmpfs 379M 12K 379M 1% /run/user/1000
/home/serge/.Private ecryptfs 79G 18G 58G 24% /home/sergeSimilar, but nicer and in colours:
$ dfc -dlT$ cat .bash_aliases
alias df='df -hlT'
alias dfc='dfc -dlT'
alias du='du -h'To show the packages consuming the most disk space, use either the dpigs command or the wajig large command:
$ sudo apt install debian-goodies
$ dpigs$ sudo apt install wajig
$ wajig largePurge removed packages
Files of previously removed packages may keep on lingering on the system. The following two commands will purge the system of these unnecessary files.
$ sudo apt autoremove
$ dpkg --list |grep "^rc" |cut -d " " -f 3 |xargs sudo dpkg --purgeSMART monitoring
The acronym SMART stands for Self-Monitoring, Analysis, and Reporting Technology. Here is how to check whether SMART is supported by a particular drive and whether SMART is switched on.
$ sudo apt install smartmontools
$ sudo smartctl -i /dev/sda
smartctl 6.5 2016-01-24 r4214 [x86_64-linux-4.4.0-34-generic] (local build)
Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF INFORMATION SECTION ===
Model Family: Seagate Barracuda 7200.8
Device Model: ST3300831AS
Serial Number: 4NF0WW20
Firmware Version: 3.03
User Capacity: 300,069,052,416 bytes [300 GB]
Sector Size: 512 bytes logical/physical
Device is: In smartctl database [for details use: -P show]
ATA Version is: ATA/ATAPI-7 (minor revision not indicated)
Local Time is: Wed Aug 24 00:02:09 2016 CEST
SMART support is: Available - device has SMART capability.
SMART support is: EnabledEnabling SMART
$ sudo smartctl -s on /dev/sda
smartctl 6.5 2016-01-24 r4214 [x86_64-linux-4.4.0-34-generic] (local build)
Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF ENABLE/DISABLE COMMANDS SECTION ===
SMART Enabled.SMART health assessment
$ sudo smartctl -H /dev/sda
smartctl 6.5 2016-01-24 r4214 [x86_64-linux-4.4.0-34-generic] (local build)
Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSEDAll SMART output
$ sudo smartctl -a /dev/sda
smartctl 6.5 2016-01-24 r4214 [x86_64-linux-4.4.0-34-generic] (local build)
Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF INFORMATION SECTION ===
Model Family: Seagate Barracuda 7200.8
Device Model: ST3300831AS
Serial Number: 4NF0WW20
Firmware Version: 3.03
User Capacity: 300,069,052,416 bytes [300 GB]
Sector Size: 512 bytes logical/physical
Device is: In smartctl database [for details use: -P show]
ATA Version is: ATA/ATAPI-7 (minor revision not indicated)
Local Time is: Wed Aug 24 00:02:17 2016 CEST
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: ( 101) 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 063 057 006 Pre-fail Always - 162822491
3 Spin_Up_Time 0x0003 097 097 000 Pre-fail Always - 0
4 Start_Stop_Count 0x0032 099 099 020 Old_age Always - 1913
5 Reallocated_Sector_Ct 0x0033 100 100 036 Pre-fail Always - 0
7 Seek_Error_Rate 0x000f 084 060 030 Pre-fail Always - 269974882
9 Power_On_Hours 0x0032 090 090 000 Old_age Always - 8792
10 Spin_Retry_Count 0x0013 100 100 097 Pre-fail Always - 0
12 Power_Cycle_Count 0x0032 099 099 020 Old_age Always - 1920
194 Temperature_Celsius 0x0022 044 052 000 Old_age Always - 44 (0 14 0 0 0)
195 Hardware_ECC_Recovered 0x001a 063 057 000 Old_age Always - 162822491
197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 0
198 Offline_Uncorrectable 0x0010 100 100 000 Old_age Offline - 0
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 Data_Address_Mark_Errs 0x0032 100 253 000 Old_age Always - 0
SMART Error Log Version: 1
No Errors Logged
SMART Self-test log structure revision number 1
Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error
# 1 Short offline Completed without error 00% 0 -
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.hddtemp
$ sudo apt install hddtemp
$ sudo hddtemp /dev/sd[abcd]
/dev/sda: WDC WD10EARS-00Y5B1: 33°C
/dev/sdb: WDC WD10EADS-00L5B1: 31°C
/dev/sdc: WDC WD10EADS-00M2B0: 33°C
/dev/sdd: Generic-SD/MMC: S.M.A.R.T. not available
$ sudo hddtemp /dev/sd*[^[:digit:]] 2>/dev/null |sort -k3rn
/dev/sda: Generic MassStorageClass: S.M.A.R.T. not available
/dev/sde: WDC WD20EFRX-68EUZN0: 35°C
/dev/sdf: WDC WD20EFRX-68EUZN0: 34°C
/dev/sdg: WDC WD20EFRX-68EUZN0: 36°CThe latter hddtemp evocation is the most useful and may be added as the default to .bash_aliases as follows:
alias hddtemp='sudo hddtemp /dev/sd*[^[:digit:]] 2>/dev/null |sort -k3rn'hdparm
Installing hdparm
On modern Debian derived distributions, hdparm can be installed as follows:
$ sudo apt install hdparmDetailed drive info from hdparm
-I: Request identification info directly from the drive, which is displayed in a new expanded format with considerably more detail than with the older -i flag.
$ sudo hdparm -I /dev/sda /dev/sda:
ATA device, with non-removable media
Model Number: WDC WD2500BEVT-08A23T1
Serial Number: WD-WXK1A8004345
Firmware Revision: 02.01A02
Transport: Serial, SATA 1.0a, SATA II Extensions, SATA Rev 2.5, SATA Rev 2.6
Standards:
Supported: 8 7 6 5
Likely used: 8
Configuration:
Logical max current
cylinders 16383 16383
heads 16 16
sectors/track 63 63
--
CHS current addressable sectors: 16514064
LBA user addressable sectors: 268435455
LBA48 user addressable sectors: 488397168
Logical/Physical Sector size: 512 bytes
device size with M = 1024*1024: 238475 MBytes
device size with M = 1000*1000: 250059 MBytes (250 GB)
cache/buffer size = 8192 KBytes
Nominal Media Rotation Rate: 5400
Capabilities:
LBA, IORDY(can be disabled)
Queue depth: 32
Standby timer values: spec'd by Standard, no device specific minimum
R/W multiple sector transfer: Max = 16 Current = 16
Advanced power management level: 127
Recommended acoustic management value: 128, current value: 128
DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6
Cycle time: min=120ns recommended=120ns
PIO: pio0 pio1 pio2 pio3 pio4
Cycle time: no flow control=120ns IORDY flow control=120ns Commands/features:
Enabled Supported:
* SMART feature set
Security Mode feature set
* Power Management feature set
* Write cache
* Look-ahead
* Host Protected Area feature set
* WRITE_BUFFER command
* READ_BUFFER command
* DOWNLOAD_MICROCODE
* Advanced Power Management feature set
SET_MAX security extension
* Automatic Acoustic Management feature set
* 48-bit Address feature set
* Device Configuration Overlay feature set
* Mandatory FLUSH_CACHE
* FLUSH_CACHE_EXT
* SMART error logging
* SMART self-test
* General Purpose Logging feature set
* WRITE_{DMA|MULTIPLE}_FUA_EXT
* 64-bit World wide name
* IDLE_IMMEDIATE with UNLOAD
* Disable Data Transfer After Error Detection
* WRITE_UNCORRECTABLE_EXT command
* {READ,WRITE}_DMA_EXT_GPL commands
* Segmented DOWNLOAD_MICROCODE
* Gen1 signaling speed (1.5Gb/s)
* Gen2 signaling speed (3.0Gb/s)
* Native Command Queueing (NCQ)
* Host-initiated interface power management
* Phy event counters
* Idle-Unload when NCQ is active
* NCQ priority information
* DMA Setup Auto-Activate optimization
* Device-initiated interface power management
* Software settings preservation
* SMART Command Transport (SCT) feature set
* SCT Read/Write Long (AC1), obsolete
* SCT Write Same (AC2)
* SCT Features Control (AC4)
* SCT Data Tables (AC5)
unknown 206[12] (vendor specific)
unknown 206[13] (vendor specific)
unknown 206[14] (vendor specific)
Security:
Master password revision code = 65534
supported
not enabled
not locked
frozen
not expired: security count
supported: enhanced erase
64min for SECURITY ERASE UNIT. 64min for ENHANCED SECURITY ERASE UNIT.
Logical Unit WWN Device Identifier: 50014ee25a524517
NAA : 5
IEEE OUI : 0014ee
Unique ID : 25a524517
Checksum: correctQuerying spin-down parameters with hdparm
Caveat: Refrain from using laptop-mode-tools
Never install
laptop-mode-tools, regardless whetherhdparmis used or not! The packagelaptop-mode-toolswill overwrite thehdparm -Boption and set it to 1. Such a setting will cause any hard drive to fail early.
-B: Query/set Advanced Power Management feature, if the drive supports it. A low value means aggressive power management and a high value means better performance. Values which permit spin-down range from 1 to 127; values 128 through 254 will not permit spin-down. The highest degree of power management is attained with a setting of 1, and the highest I/O performance with a setting of 254. A value of 255 tells hdparm to disable Advanced Power Management altogether on the drive. Not all drives support disabling it, but most do.
-S: Put the drive into idle (low-power) mode, and also set the standby (spin-down) timeout for the drive. This timeout value is used by the drive to determine how long to wait after the last disk activity before turning off the spindle motor to save power. Once spun down, a drive may take as long as 30 seconds to respond to a subsequent disk access, though most drives are much quicker. The encoding of the timeout value is somewhat peculiar:
- The value of 0 disables any timeout; The device will refrain from automatically entering standby mode.
- Values from 1 to 240 specify multiples of 5 seconds, yielding timeouts from 5 seconds to 20 minutes.
- Values from 241 to 251 specify from 1 to 11 units of 30 minutes, yielding timeouts from 30 minutes to 5.5 hours.
- A value of 252 signifies a timeout of 21 minutes.
- A value of 253 sets a vendor-defined timeout period between 8 and 12 hours.
- The value of 254 is reserved.
- A value of 255 is interpreted as 21 minutes plus 15 seconds.
Note that some older drives may have very different interpretations of these values.
Setting spin-down parameters with hdparm
$ sudo hdparm -B127 /dev/sda
/dev/sda:
setting Advanced Power Management level to 0x7f (127)
APM_level = 127$ sudo hdparm -S60 /dev/sda
/dev/sda:
setting standby to 60 (5 minutes)5
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Last update: Tuesday, October 11, 2022.