{"id":279,"date":"2009-01-15T05:29:28","date_gmt":"2009-01-15T11:29:28","guid":{"rendered":"http:\/\/blog.supportpro.com\/?p=279"},"modified":"2026-03-25T04:40:12","modified_gmt":"2026-03-25T10:40:12","slug":"smartd-a-brief-intro","status":"publish","type":"post","link":"https:\/\/www.supportpro.com\/blog\/smartd-a-brief-intro\/","title":{"rendered":"S.M.A.R.T.D \u2013 SMART Disk Monitoring Daemon"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\"><strong><span style=\"color: revert; font-size: revert;\">What Is smartd?<\/span><\/strong><\/h2>\n\n\n\n<p><strong data-start=\"268\" data-end=\"278\">smartd<\/strong> stands for <strong data-start=\"290\" data-end=\"322\">SMART Disk Monitoring Daemon<\/strong>. It is part of the <strong data-start=\"342\" data-end=\"359\">smartmontools<\/strong> package and continuously monitors the <strong data-start=\"398\" data-end=\"460\">SMART (Self-Monitoring, Analysis and Reporting Technology)<\/strong> system built into modern hard drives and SSDs.<\/p>\n\n\n\n<p>SMART helps detect and report early warning signs of disk failure. By monitoring these indicators, smartd allows administrators to take preventive action before data loss occurs.<\/p>\n\n\n\n<p>smartd supports:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p data-start=\"708\" data-end=\"728\">SATA and ATA disks<\/p><\/li>\n\n\n\n<li><p data-start=\"731\" data-end=\"743\">SCSI disks<\/p><\/li>\n\n\n\n<li><p data-start=\"746\" data-end=\"792\">Many SSDs and NVMe drives (limited attributes)<\/p><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">How SMART Works<\/h2>\n\n\n\n<p>SMART tracks several health indicators such as:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p data-start=\"869\" data-end=\"890\">Reallocated sectors<\/p><\/li>\n\n\n\n<li><p data-start=\"893\" data-end=\"916\">Read and write errors<\/p><\/li>\n\n\n\n<li><p data-start=\"919\" data-end=\"932\">Temperature<\/p><\/li>\n\n\n\n<li><p data-start=\"935\" data-end=\"951\">Power-on hours<\/p><\/li>\n\n\n\n<li><p data-start=\"954\" data-end=\"977\">Pending sector counts<\/p><\/li>\n<\/ul>\n\n\n\n<p>When these values exceed safe thresholds, smartd can generate warnings via system logs or email notifications.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">smartmontools Project<\/h2>\n\n\n\n<p>smartd is maintained as part of the <strong data-start=\"1158\" data-end=\"1175\">smartmontools<\/strong> open-source project.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Key Contributors<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p data-start=\"1221\" data-end=\"1258\"><strong data-start=\"1221\" data-end=\"1236\">Bruce Allen<\/strong> \u2013 Project initiator<\/p><\/li>\n\n\n\n<li><p data-start=\"1261\" data-end=\"1315\"><strong data-start=\"1261\" data-end=\"1281\">Christian Franke<\/strong> \u2013 Lead developer and maintainer<\/p><\/li>\n<\/ul>\n\n\n\n<p>The project is actively maintained and widely used across Linux, BSD, macOS, and Windows.<\/p>\n\n\n\n<p>Project site:<br data-start=\"1421\" data-end=\"1424\"><a class=\"decorated-link\" href=\"https:\/\/sourceforge.net\/projects\/smartmontools\/\" target=\"_new\" rel=\"noopener\" data-start=\"1424\" data-end=\"1471\">https:\/\/sourceforge.net\/projects\/smartmontools\/<\/a><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Installing smartmontools<\/h2>\n\n\n\n<h4 class=\"wp-block-heading\">On Debian \/ Ubuntu<\/h4>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"sticky top-[calc(--spacing(9)+var(--header-height))] @w-xl\/main:top-9\">\n<div class=\"absolute end-0 bottom-0 flex h-9 items-center pe-2\">\n<div class=\"bg-token-bg-elevated-secondary text-token-text-secondary flex items-center gap-4 rounded-sm px-2 font-sans text-xs\"><em><strong>&nbsp;| apt install smartmontools<\/strong><\/em><\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">&nbsp;<\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">On RHEL \/ CentOS \/ Rocky \/ AlmaLinux<\/h4>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| dnf install smartmontools<\/strong><\/em><\/div>\n<div dir=\"ltr\">&nbsp;<\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\">SMARTD Binary Path<\/h2>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| \/usr\/sbin\/smartd<\/strong><\/em><\/div>\n<div dir=\"ltr\">&nbsp;<\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Check if a Disk Supports SMART<\/h2>\n\n\n\n<p>First, identify your disk:<\/p>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| lsblk<\/strong><\/em><\/div>\n<div dir=\"ltr\">&nbsp;<\/div>\n<\/div>\n\n\n\n<p>Then run:<\/p>\n\n\n\n<p><em style=\"font-size: revert;\"><strong>| smartctl -i \/dev\/sda<\/strong><\/em><\/p>\n\n\n\n<p>If the disk supports SMART, you will see:<\/p>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| SMART support is: Available<\/strong><\/em><br><em><strong>| SMART support is: Enabled<\/strong><\/em><\/div>\n<\/div>\n\n\n\n<div dir=\"ltr\">&nbsp;<\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Enable and Manage smartd (systemd)<\/h2>\n\n\n\n<h4 class=\"wp-block-heading\">Enable smartd at boot<\/h4>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| systemctl enable smartd<\/strong><\/em><\/div>\n<div dir=\"ltr\">&nbsp;<\/div>\n<\/div>\n\n\n\n<h4 class=\"wp-block-heading\">Start smartd<\/h4>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| systemctl start smartd<\/strong><\/em><\/div>\n<div dir=\"ltr\">&nbsp;<\/div>\n<\/div>\n\n\n\n<h4 class=\"wp-block-heading\">Stop smartd<\/h4>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| systemctl stop smartd<\/strong><\/em><\/div>\n<div dir=\"ltr\">&nbsp;<\/div>\n<h4 dir=\"ltr\"><span style=\"color: revert; font-size: revert; font-weight: revert;\">Check status<\/span><\/h4>\n<\/div>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| systemctl status smartd<\/strong><\/em><\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Logging and Configuration<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p data-start=\"2257\" data-end=\"2278\">Default log location:<\/p><\/li>\n<\/ul>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"sticky top-[calc(--spacing(9)+var(--header-height))] @w-xl\/main:top-9\">&nbsp;<\/div>\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| \/var\/log\/messages<\/strong><\/em><\/div>\n<\/div>\n\n\n\n<p>(or <strong>journalctl<\/strong> on systemd systems)<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p data-start=\"2349\" data-end=\"2368\">Configuration file:<\/p><\/li>\n<\/ul>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"sticky top-[calc(--spacing(9)+var(--header-height))] @w-xl\/main:top-9\">&nbsp;<\/div>\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| \/etc\/smartd.conf<\/strong><\/em><\/div>\n<\/div>\n\n\n\n<p>smartd checks disk health approximately <strong data-start=\"2439\" data-end=\"2459\">every 30 minutes<\/strong> by default. This interval can be customized in the configuration file.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Checking Disk Health Manually<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Overall SMART health status<\/h3>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| smartctl -H \/dev\/sda<\/strong><\/em><\/div>\n<div dir=\"ltr\">&nbsp;<\/div>\n<\/div>\n\n\n\n<h3 class=\"wp-block-heading\">View vendor-specific SMART attributes<\/h3>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| smartctl -A \/dev\/sda<\/strong><\/em><\/div>\n<div dir=\"ltr\">&nbsp;<\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Sample smartd.conf Entries<\/h2>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| \/dev\/sda -a -m admin@example.com<\/strong><\/em><br><em><strong>| \/dev\/sdb -a -I 194 -s L\/..\/..\/7\/03<\/strong><\/em><\/div>\n<div dir=\"ltr\">&nbsp;<\/div>\n<\/div>\n\n\n\n<p>These options:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p data-start=\"2849\" data-end=\"2874\">Enable all SMART checks<\/p><\/li>\n\n\n\n<li><p data-start=\"2877\" data-end=\"2905\">Ignore selected attributes<\/p><\/li>\n\n\n\n<li><p data-start=\"2908\" data-end=\"2929\">Schedule self-tests<\/p><\/li>\n\n\n\n<li><p data-start=\"2932\" data-end=\"2951\">Send email alerts<\/p><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Force smartd to Check Disk Health<\/h2>\n\n\n\n<p>The superuser can force an immediate check:<\/p>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| kill -USR1 $(pidof smartd)<\/strong><\/em><\/div>\n<div dir=\"ltr\">&nbsp;<\/div>\n<\/div>\n\n\n\n<p>or<\/p>\n\n\n\n<div class=\"contain-inline-size rounded-2xl corner-superellipse\/1.1 relative bg-token-sidebar-surface-primary\">\n<div class=\"overflow-y-auto p-4\" dir=\"ltr\"><em><strong>| killall -USR1 smartd<\/strong><\/em><\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Advantages of smartd<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p data-start=\"3151\" data-end=\"3186\">Continuous disk health monitoring<\/p><\/li>\n\n\n\n<li><p data-start=\"3189\" data-end=\"3226\">Early warning of potential failures<\/p><\/li>\n\n\n\n<li><p data-start=\"3229\" data-end=\"3257\">Email and log-based alerts<\/p><\/li>\n\n\n\n<li><p data-start=\"3260\" data-end=\"3300\">Works with most modern storage devices<\/p><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Limitations of SMART<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p data-start=\"3334\" data-end=\"3369\">SMART cannot predict all failures<\/p><\/li>\n\n\n\n<li><p data-start=\"3372\" data-end=\"3440\">Sudden electronic or mechanical failures may occur without warning<\/p><\/li>\n\n\n\n<li><p data-start=\"3443\" data-end=\"3517\">SMART should be used <strong data-start=\"3464\" data-end=\"3493\">alongside regular backups<\/strong>, not as a replacement<\/p><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">References<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p data-start=\"3541\" data-end=\"3558\">smartd man page<\/p><\/li>\n\n\n\n<li><p data-start=\"3561\" data-end=\"3608\"><a class=\"decorated-link\" data-start=\"3561\" data-end=\"3608\" href=\"https:\/\/sourceforge.net\/projects\/smartmontools\/\" target=\"_new\" rel=\"noopener\">https:\/\/sourceforge.net\/projects\/smartmontools\/<\/a><\/p><\/li>\n<\/ul>\n\n\n\n<p>If you require help, <a href=\"https:\/\/www.supportpro.com\/requestquote.php\">contact SupportPRO Server Admin<\/a><span 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class=\"wp-image-12943 size-full\" srcset=\"https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2022\/09\/Free-server-checkup.png 904w, https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2022\/09\/Free-server-checkup-291x300.png 291w, https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2022\/09\/Free-server-checkup-768x791.png 768w, https:\/\/www.supportpro.com\/blog\/wp-content\/uploads\/2022\/09\/Free-server-checkup-585x602.png 585w\" sizes=\"(max-width: 904px) 100vw, 904px\" \/><\/figure><\/div>\n","protected":false},"excerpt":{"rendered":"<p>What Is smartd? smartd stands for SMART Disk Monitoring Daemon. It is part of the smartmontools package and continuously monitors the SMART (Self-Monitoring, Analysis and Reporting Technology) system built into&hellip;<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_lmt_disableupdate":"","_lmt_disable":"","footnotes":""},"categories":[3],"tags":[],"class_list":["post-279","post","type-post","status-publish","format-standard","hentry","category-technical-articles"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/posts\/279","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/comments?post=279"}],"version-history":[{"count":14,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/posts\/279\/revisions"}],"predecessor-version":[{"id":16591,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/posts\/279\/revisions\/16591"}],"wp:attachment":[{"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/media?parent=279"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/categories?post=279"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.supportpro.com\/blog\/wp-json\/wp\/v2\/tags?post=279"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}