How to check disk health status in Linux
Monitoring disk health in Linux reduces the risk of sudden data loss by revealing failing HDDs and SSDs before they stop responding. Early detection allows storage to be replaced during maintenance windows instead of during outages, keeping services and personal files available.
Disk firmware exposes internal health metrics through S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology). On Linux these metrics are typically accessed with the smartctl utility from the smartmontools package, which can read attributes, run built-in self-tests, and show overall health summaries for devices such as /dev/sda or /dev/nvme0n1.
S.M.A.R.T. cannot detect every failure mode and does not substitute for regular backups, filesystem checks, or RAID monitoring. Some controllers or virtual disks may not expose full data, and intensive self-tests can temporarily impact performance on busy systems. The steps below focus on a short, non-destructive check on Ubuntu or other Debian-based distributions with root privileges available through sudo.
Related: How to check disk errors in Linux
Related: How to mount disks and partitions in Linux
Steps to check hard drive health status in Linux:
- Open a terminal session on the Linux system.
- Refresh package metadata before installing disk utilities.
$ sudo apt update WARNING: apt does not have a stable CLI interface. Use with caution in scripts. Hit:1 http://ports.ubuntu.com/ubuntu-ports noble InRelease Hit:2 http://ports.ubuntu.com/ubuntu-ports noble-updates InRelease Hit:3 http://ports.ubuntu.com/ubuntu-ports noble-backports InRelease Hit:4 http://ports.ubuntu.com/ubuntu-ports noble-security InRelease Reading package lists... Building dependency tree... Reading state information... 5 packages can be upgraded. Run 'apt list --upgradable' to see them.
- Install the smartmontools package from the distribution repository.
$ sudo apt install --assume-yes smartmontools WARNING: apt does not have a stable CLI interface. Use with caution in scripts. Reading package lists... Building dependency tree... Reading state information... smartmontools is already the newest version (7.4-2build1). 0 upgraded, 0 newly installed, 0 to remove and 5 not upgraded.
On Debian and Ubuntu, smartmontools provides the smartctl command; other distributions use package managers such as dnf, zypper, or pacman to install the same package.
- List block devices to identify the target disk name.
$ lsblk -d -o NAME,TYPE,SIZE | grep -E 'disk|nvme' nbd0 disk 0B nbd1 disk 0B nbd2 disk 0B nbd3 disk 0B nbd4 disk 0B nbd5 disk 0B nbd6 disk 0B nbd7 disk 0B vda disk 1.8T vdb disk 606.5M nbd8 disk 0B nbd9 disk 0B nbd10 disk 0B nbd11 disk 0B nbd12 disk 0B nbd13 disk 0B nbd14 disk 0B nbd15 disk 0B
This output shows classic SATA disks such as /dev/sda as well as any NVMe disks when present; the appropriate device name is required for later commands.
- Query basic information on the selected disk to confirm that S.M.A.R.T. support is enabled.
$ sudo smartctl -i /dev/vdb smartctl 7.4 2023-08-01 r5530 [aarch64-linux-6.12.54-linuxkit] (local build) Copyright (C) 2002-23, Bruce Allen, Christian Franke, www.smartmontools.org /dev/vdb: Unable to detect device type Please specify device type with the -d option. Use smartctl -h to get a usage summary
Proceed only when the output shows that S.M.A.R.T. support is available and enabled; some virtual disks or USB adapters may not expose these capabilities.
- Start a short S.M.A.R.T. self-test on the selected disk.
$ sudo smartctl -t short /dev/vdb smartctl 7.4 2023-08-01 r5530 [aarch64-linux-6.12.54-linuxkit] (local build) Copyright (C) 2002-23, Bruce Allen, Christian Franke, www.smartmontools.org /dev/vdb: Unable to detect device type Please specify device type with the -d option. Use smartctl -h to get a usage summary
Short self-tests are non-destructive but can still impact performance, so running tests on busy production disks may cause higher latency or temporary slowdowns.
- Display the overall S.M.A.R.T. health status after the short test completes.
$ sudo smartctl -H /dev/vdb smartctl 7.4 2023-08-01 r5530 [aarch64-linux-6.12.54-linuxkit] (local build) Copyright (C) 2002-23, Bruce Allen, Christian Franke, www.smartmontools.org /dev/vdb: Unable to detect device type Please specify device type with the -d option. Use smartctl -h to get a usage summary
A result such as PASSED or OK indicates that the disk firmware does not currently consider the device to be failing, although backups remain essential.
- Inspect detailed S.M.A.R.T. attributes to spot reallocated sectors or read errors.
$ sudo smartctl -a /dev/vdb smartctl 7.4 2023-08-01 r5530 [aarch64-linux-6.12.54-linuxkit] (local build) Copyright (C) 2002-23, Bruce Allen, Christian Franke, www.smartmontools.org /dev/vdb: Unable to detect device type Please specify device type with the -d option. Use smartctl -h to get a usage summary
Growing counts for attributes such as Reallocated_Sector_Ct or Current_Pending_Sector often indicate impending failure even when the overall health status still shows PASSED.
- Review the S.M.A.R.T. self-test log to confirm that recent tests completed without error.
$ sudo smartctl -l selftest /dev/vdb smartctl 7.4 2023-08-01 r5530 [aarch64-linux-6.12.54-linuxkit] (local build) Copyright (C) 2002-23, Bruce Allen, Christian Franke, www.smartmontools.org /dev/vdb: Unable to detect device type Please specify device type with the -d option. Use smartctl -h to get a usage summary
A status of Completed without error for the most recent entry verifies that the short self-test finished successfully.
- Retry with an explicit device type when working with passthrough or virtual disks.
$ sudo smartctl -a -d scsi -T permissive /dev/vdb smartctl 7.4 2023-08-01 r5530 [aarch64-linux-6.12.54-linuxkit] (local build) Copyright (C) 2002-23, Bruce Allen, Christian Franke, www.smartmontools.org Standard Inquiry (36 bytes) failed [Inappropriate ioctl for device] Retrying with a 64 byte Standard Inquiry Standard Inquiry (64 bytes) failed [Inappropriate ioctl for device] === START OF READ SMART DATA SECTION === Request Sense failed, [Inappropriate ioctl for device] Read defect list: asked for grown list but didn't get it Error Counter logging not supported Device does not support Self Test logging
If the disk still does not report S.M.A.R.T. data, it may be a virtual device or controller that does not expose health metrics; check the host or use physical hardware for SMART checks.