# Monitor SMART with Nightingale Runs smartctl to read S.M.A.R.T. health attributes from HDDs, SSDs and NVMe drives, so you see reallocated sectors, temperature and wear before a disk actually dies. Last reviewed 2026-10-13 S.M.A.R.T. is the self-monitoring built into hard drives and SSDs. The Categraf smart input runs `smartctl` (and the `nvme` tool for NVMe devices) and emits `smart_device` for overall health plus `smart_attribute` for individual attributes: reallocated sectors, pending sectors, temperature, power-on hours, SSD wear and more. The bundled rules watch the precursors of data loss: failed health checks, growing reallocated-sector counts and high temperature. The host needs smartmontools installed and Categraf needs permission to run smartctl, usually via passwordless sudo. ## What's in the template[​](#whats-in-the-template "Direct link to What's in the template") * **1 dashboard**, 20 panels in total * **6 alert rules**, each with runbook steps * **14 metric descriptions** * **Categraf collector config**: `input.smart` ## How to connect[​](#how-to-connect "Direct link to How to connect") 1. [Install Categraf](https://n9e.github.io/docs/data/categraf/install.md), put the config below in `conf/input.smart/smart.toml`, fill in your own address and credentials, and restart Categraf. The startup log prints `input: local.smart started` once the plugin is loaded. ``` # Read metrics from storage devices supporting S.M.A.R.T. [[instances]] ## Optionally specify the path to the smartctl executable # path_smartctl = "/usr/bin/smartctl" ## Optionally specify the path to the nvme-cli executable # path_nvme = "/usr/bin/nvme" ## Optionally specify if vendor specific attributes should be propagated for NVMe disk case ## ["auto-on"] - automatically find and enable additional vendor specific disk info ## ["vendor1", "vendor2", ...] - e.g. "Intel" enable additional Intel specific disk info # enable_extensions = ["auto-on"] ## On most platforms used cli utilities requires root access. ## Setting 'use_sudo' to true will make use of sudo to run smartctl or nvme-cli. ## Sudo must be configured to allow the telegraf user to run smartctl or nvme-cli ## without a password. # use_sudo = true ## Skip checking disks in this power mode. Defaults to ## "standby" to not wake up disks that have stopped rotating. ## See --nocheck in the man pages for smartctl. ## smartctl version 5.41 and 5.42 have faulty detection of ## power mode and might require changing this value to ## "never" depending on your disks. # nocheck = "standby" ## Gather all returned S.M.A.R.T. attribute metrics and the detailed ## information from each drive into the 'smart_attribute' measurement. # attributes = true ## Optionally specify devices to exclude from reporting if disks auto-discovery is performed. # excludes = [ "/dev/pass6" ] ## Optionally specify devices and device type, if unset ## a scan (smartctl --scan and smartctl --scan -d nvme) for S.M.A.R.T. devices will be done ## and all found will be included except for the excluded in excludes. # devices = [ "/dev/ada0 -d atacam", "/dev/nvme0"] # devices = ["dev/nvme0 -d nvme", "/dev/nvme0"] ## Timeout for the cli command to complete. timeout = "30s" ## Optionally call smartctl and nvme-cli with a specific concurrency policy. ## By default, smartctl and nvme-cli are called in separate threads (goroutines) to gather disk attributes. ## Some devices (e.g. disks in RAID arrays) may have access limitations that require sequential reading of ## SMART data - one individual array drive at the time. In such case please set this configuration option ## to "sequential" to get readings for all drives. ## valid options: concurrent, sequential # read_method = "concurrent" ``` 2. Open the integration center in Nightingale, find SMART, and [import the dashboards and alert rules](https://n9e.github.io/docs/data/integrations/import.md) into a business group. 3. Imported rules start disabled. [Check that the metrics are arriving](https://n9e.github.io/docs/data/integrations/verify.md) first, then enable the rules one by one with thresholds that fit your environment. ## Bundled dashboards[​](#bundled-dashboards "Direct link to Bundled dashboards") | Dashboard | Panels | | ------------------- | ------ | | S.M.A.R.T Dashboard | 20 | ## Bundled alert rules[​](#bundled-alert-rules "Direct link to Bundled alert rules") 6 rules. Each lists its trigger condition (PromQL) and the steps to take when it fires. Thresholds are meant to be adjusted after import. ### SMART device health status abnormal[​](#smart-device-health-status-abnormal "Direct link to SMART device health status abnormal") Disk self-assessed overall health is FAILED, serious failure risk, handle immediately S1 Critical · for 1 min · Trigger: ``` smart_device_health_ok == 0 ``` Runbook: 1. Run smartctl -a /dev/sdX for the full attribute list, focusing on Reallocated\_Sector\_Ct, Current\_Pending\_Sector and Offline\_Uncorrectable; 2. Immediately confirm the data on this disk has a replica or backup — this is the highest priority action; 3. In a RAID array, check the array state and let it evict this disk and rebuild onto a hot spare; 4. Schedule downtime to replace the disk and stop writing to it. ### SSD media wearout >= 90%[​](#ssd-media-wearout--90 "Direct link to SSD media wearout >= 90%") SSD flash wearout is nearly exhausted and may fail at any time; back up data and replace the drive immediately S1 Critical · for 1 min · Trigger: ``` smart_attribute_media_wear_percentage >= 90 ``` Runbook: 1. Run smartctl -a /dev/sdX and check Media\_Wearout\_Indicator / Percentage\_Used together with Total\_LBAs\_Written; 2. Combine with the write rate to estimate remaining life and plan the replacement window; 3. Confirm the data on this disk has a replica and prepare the migration plan in advance; 4. Review the source of write amplification (log level, frequent small writes, no TRIM) so the replacement does not repeat it. ### Disk temperature exceeds 65 Celsius[​](#disk-temperature-exceeds-65-celsius "Direct link to Disk temperature exceeds 65 Celsius") Disk operating temperature too high, which accelerates aging or causes outright failure; check cooling immediately S1 Critical · for 3 min · Trigger: ``` smart_device_temp_c > 65 ``` Runbook: 1. Run smartctl -a /dev/sdX and compare the temperature against the vendor's rated maximum; 2. Check chassis airflow, fan speeds and dust in the filters, plus the room's ambient temperature; 3. Check whether the bay layout is too dense and whether neighbouring disks are equally hot; 4. Short term, reduce IO pressure on this disk (shift backups off peak, move hot data) to buy time. ### CRC error count keeps growing within 1 hour[​](#crc-error-count-keeps-growing-within-1-hour "Direct link to CRC error count keeps growing within 1 hour") Growing CRC failures on the data link, a possible precursor of interface, cable or disk controller failure S1 Critical · for 60 min · Trigger: ``` increase(smart_attribute_crc_error_count[1h]) > 0 ``` Runbook: 1. Run smartctl -a /dev/sdX and check how fast UDMA\_CRC\_Error\_Count is growing; 2. Take the machine down, reseat the SATA/SAS data and power cables, and preferably just replace the cable; 3. After replacing the cable, watch whether the counter stops growing — SMART counters never reset, so judge by the delta, not the absolute value; 4. If a new cable does not help, suspect the backplane or HBA and swap them one at a time. ### SSD erase fail count growing[​](#ssd-erase-fail-count-growing "Direct link to SSD erase fail count growing") SSD flash block erase failures indicate aging flash chips and a risk of write failures S1 Critical · for 1 min · Trigger: ``` increase(smart_attribute_erase_fail_count[1h]) > 0 ``` Runbook: 1. Run smartctl -a /dev/sdX and check Erase\_Fail\_Count together with the remaining Reallocated/Available\_Reservd\_Space; 2. A shrinking spare block pool means the disk is near end of life — confirm the data has a replica immediately; 3. Schedule a replacement rather than waiting for writes to fail outright; 4. Reduce write pressure on the disk beforehand so it does not degrade faster. ### SSD program fail count growing[​](#ssd-program-fail-count-growing "Direct link to SSD program fail count growing") SSD flash block program failures; flash chip health is degrading rapidly, back up data immediately S1 Critical · for 1 min · Trigger: ``` increase(smart_attribute_program_fail_count[1h]) > 0 ``` Runbook: 1. Run smartctl -a /dev/sdX and check Program\_Fail\_Count together with the remaining spare block ratio; 2. Immediately confirm the data on this disk has a replica or backup — this is the highest priority action; 3. Schedule a replacement soon: program failures often come with a risk of silent data corruption; 4. Before replacing it, make the disk read-only or move hot data off to stop further writes. ## Metric reference[​](#metric-reference "Direct link to Metric reference") 14 metrics, the ones the dashboards and rules above are built on. | Metric | Meaning | Unit | | -------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ---- | | `smart_attribute_crc_error_count` | SMART CRC Error Count — The number of Cyclic Redundancy Check (CRC) failures during hard disk data transmission, reflecting the reliability of the data transmission link. | | | `smart_attribute_end_to_end_error_detection_count` | SMART End-to-End Error Detection Count — The number of end-to-end verification failures in internal hard disk data transmission, associated with the health of hard disk firmware or physical storage units. | | | `smart_attribute_erase_fail_count` | SMART Erase Fail Count — The number of failures when a Solid State Drive (SSD) erases flash memory blocks; an excessive number may indicate flash chip aging or an increase in bad blocks. | | | `smart_attribute_host_reads` | SMART Host Reads Count — The total number of times the operating system reads data from the hard disk, which is a statistical indicator of hard disk usage with no direct fault warning significance. | | | `smart_attribute_media_wear_percentage` | SMART Media Wear Percentage — A core indicator dedicated to Solid State Drives (SSDs) that reflects the wear level of flash memory chips; the closer the value is to 100%, the shorter the lifespan. | % | | `smart_attribute_pll_lock_loss_count` | SMART PLL Lock Loss Count — The number of times the hard disk clock synchronization module (Phase-Locked Loop, PLL) loses lock, which can cause data transmission timing errors. | | | `smart_attribute_program_fail_count` | SMART Program Fail Count — The number of failures when a Solid State Drive (SSD) writes data (program operation) to flash memory blocks, which is a core indicator of flash memory health. | | | `smart_attribute_retry_buffer_overflow_count` | SMART Retry Buffer Overflow Count — The number of times the data buffer overflows when the hard disk automatically retries after a read/write failure, indicating a decline in hard disk read/write performance or hardware failure. | | | `smart_attribute_thermal_throttle_status` | SMART Thermal Throttle Status — The state where the hard disk triggers automatic speed reduction protection due to high temperature (1=triggered, 0=not triggered), which will cause slow read/write speeds after triggering. | | | `smart_attribute_timed_workload_timer` | SMART Timed Workload Timer — Accumulates the operating time of the hard disk in a preset load mode, used to evaluate the long-term working intensity of the hard disk and assist in judging the wear rate. | s | | `smart_attribute_wear_leveling_count` | SMART Wear Leveling Count — An indicator dedicated to Solid State Drives (SSDs) that records the number of executions of the wear leveling algorithm to ensure uniform wear of flash memory blocks and extend lifespan. | | | `smart_device_exit_status` | SMART Device Exit Status — The exit status code of the hard disk SMART self-test; 0 means the self-test is completed normally, and a non-zero value indicates self-test interruption or abnormality. | | | `smart_device_health_ok` | SMART Device Health Status — The overall health status identifier of the hard disk; 1=healthy (no fault warning), 0=unhealthy (potential faults exist). | | | `smart_device_temp_c` | SMART Device Temperature — The current operating temperature of the hard disk (in ℃); the safe operating range for mainstream hard disks is 0-60℃, and prolonged overheating will accelerate hardware aging. | ℃ | ## Related[​](#related "Direct link to Related") * [SMART template source](https://github.com/ccfos/nightingale/tree/main/integrations/SMART): the raw JSON for dashboards, rules and collector config. Pull requests welcome. * [Categraf `smart` plugin docs](https://github.com/flashcatcloud/categraf/tree/main/inputs/smart): every config option and the full metric list. * [Import dashboards and alert rules](https://n9e.github.io/docs/data/integrations/import.md) * [Verify that metrics are stored](https://n9e.github.io/docs/data/integrations/verify.md) * [All integrations](https://n9e.github.io/integrations.md)