Bottom line: Include the temperature-observation gap in the disk power decision. Keep standby timing, APM idle behavior and the storage owner’s monitoring requirements as separate entries.
\nThe TrueNAS 25.10 Disks reference defines HDD Standby as an inactivity interval and uses Always On as its default. Temperature monitoring is disabled for disks in standby. The APM setting controls idle power-management behavior rather than maximum performance capability; actively accessed drives operate at full performance regardless of that setting. Bulk Edit Disks changes multiple disks together and lists the selected device names in Disks to be edited.
\nThis article reviews a documented power and monitoring tradeoff, not drive qualification or a guarantee of energy savings. It does not equate an absent temperature reading with a healthy disk or prescribe a universal standby interval.
\nThe following steps are DSE recommendations based on the cited source.
\nDSE recommends documenting the monitoring requirement before selecting a standby interval. Ask the storage owner to decide whether the proposed temperature-observation gap is acceptable for the named disks. Keep that decision separate from a general desire to reduce power use, and do not claim a saving without a measured comparison.
\nInventory the selected device names and current settings with a second operator. Review the installed-release procedure and the edit eligibility of the actual devices before applying a bulk change. Keep different drive populations and workload requirements distinct rather than approving every disk merely because the interface offers a shared selection.
\nPrepare an isolated trial with an owner-approved idle period and a harmless access workload. Record the expected monitoring observations and acceptable application behavior in advance. Treat standby timing and APM choice as separate variables so an unexplained change is not attributed to both settings without evidence.
\nAgree who investigates an unexpected temperature gap or workload interruption and who can restore the prior settings. Preserve the starting device list and configuration. Avoid interpreting a quieter monitoring display as an improved hardware condition, and keep drive health diagnosis within the separately reviewed storage process.
\nProposed verification: inspect the selected disk identities and effective standby and APM settings against the plan. During the approved idle and access periods, retain the actual temperature observations and timestamps without supplying invented readings for gaps. Compare the harmless workload results with the owner’s written acceptance criteria.
\nReview the configured population again after any bulk edit and account for every selected device. Retain actual power measurements only if an appropriate separate measurement plan was performed. Have the storage and monitoring owners accept the observed tradeoff together, leaving unexplained gaps or device behavior open instead of prescribing a universal standby value.
\nSource review completed October 30, 2026. Recheck the official documentation and deployment-specific applicability before a production change.
\n", "content_text": "Bottom line: Include the temperature-observation gap in the disk power decision. Keep standby timing, APM idle behavior and the storage owner’s monitoring requirements as separate entries.\nSource fact: what the authority says\nThe TrueNAS 25.10 Disks reference defines HDD Standby as an inactivity interval and uses Always On as its default. Temperature monitoring is disabled for disks in standby. The APM setting controls idle power-management behavior rather than maximum performance capability; actively accessed drives operate at full performance regardless of that setting. Bulk Edit Disks changes multiple disks together and lists the selected device names in Disks to be edited.\nWhat the source does not establish\nThis article reviews a documented power and monitoring tradeoff, not drive qualification or a guarantee of energy savings. It does not equate an absent temperature reading with a healthy disk or prescribe a universal standby interval.\nApplicability questions\n\nWhich exact disks and workloads are included in the power-policy proposal?\nWhat standby interval and APM setting are currently configured?\nWhat temperature observations does the monitoring owner require?\nWho will review gaps and the actual effect of an approved isolated trial?\n\nDSE recommendation: controlled next steps\nThe following steps are DSE recommendations based on the cited source.\nDSE recommends documenting the monitoring requirement before selecting a standby interval. Ask the storage owner to decide whether the proposed temperature-observation gap is acceptable for the named disks. Keep that decision separate from a general desire to reduce power use, and do not claim a saving without a measured comparison.\nInventory the selected device names and current settings with a second operator. Review the installed-release procedure and the edit eligibility of the actual devices before applying a bulk change. Keep different drive populations and workload requirements distinct rather than approving every disk merely because the interface offers a shared selection.\nPrepare an isolated trial with an owner-approved idle period and a harmless access workload. Record the expected monitoring observations and acceptable application behavior in advance. Treat standby timing and APM choice as separate variables so an unexplained change is not attributed to both settings without evidence.\nAgree who investigates an unexpected temperature gap or workload interruption and who can restore the prior settings. Preserve the starting device list and configuration. Avoid interpreting a quieter monitoring display as an improved hardware condition, and keep drive health diagnosis within the separately reviewed storage process.\nVerification and evidence\nProposed verification: inspect the selected disk identities and effective standby and APM settings against the plan. During the approved idle and access periods, retain the actual temperature observations and timestamps without supplying invented readings for gaps. Compare the harmless workload results with the owner’s written acceptance criteria.\nReview the configured population again after any bulk edit and account for every selected device. Retain actual power measurements only if an appropriate separate measurement plan was performed. Have the storage and monitoring owners accept the observed tradeoff together, leaving unexplained gaps or device behavior open instead of prescribing a universal standby value.\nOfficial references\n\nTrueNAS — Disks — official product documentation; confirm the installed release and configuration.\n\nSource review completed October 30, 2026. Recheck the official documentation and deployment-specific applicability before a production change.", "content_markdown": "Bottom line: Include the temperature-observation gap in the disk power decision. Keep standby timing, APM idle behavior and the storage owner’s monitoring requirements as separate entries.\n\n## Source fact: what the authority says\n\nThe [TrueNAS 25.10 Disks reference](https://www.truenas.com/docs/scale/25.10/scaleuireference/storage/disksscreen/) defines HDD Standby as an inactivity interval and uses Always On as its default. Temperature monitoring is disabled for disks in standby. The APM setting controls idle power-management behavior rather than maximum performance capability; actively accessed drives operate at full performance regardless of that setting. Bulk Edit Disks changes multiple disks together and lists the selected device names in Disks to be edited.\n\n## What the source does not establish\n\nThis article reviews a documented power and monitoring tradeoff, not drive qualification or a guarantee of energy savings. It does not equate an absent temperature reading with a healthy disk or prescribe a universal standby interval.\n\n## Applicability questions\n\n- Which exact disks and workloads are included in the power-policy proposal?\n\n- What standby interval and APM setting are currently configured?\n\n- What temperature observations does the monitoring owner require?\n\n- Who will review gaps and the actual effect of an approved isolated trial?\n\n## DSE recommendation: controlled next steps\n\nThe following steps are DSE recommendations based on the cited source.\n\nDSE recommends documenting the monitoring requirement before selecting a standby interval. Ask the storage owner to decide whether the proposed temperature-observation gap is acceptable for the named disks. Keep that decision separate from a general desire to reduce power use, and do not claim a saving without a measured comparison.\n\nInventory the selected device names and current settings with a second operator. Review the installed-release procedure and the edit eligibility of the actual devices before applying a bulk change. Keep different drive populations and workload requirements distinct rather than approving every disk merely because the interface offers a shared selection.\n\nPrepare an isolated trial with an owner-approved idle period and a harmless access workload. Record the expected monitoring observations and acceptable application behavior in advance. Treat standby timing and APM choice as separate variables so an unexplained change is not attributed to both settings without evidence.\n\nAgree who investigates an unexpected temperature gap or workload interruption and who can restore the prior settings. Preserve the starting device list and configuration. Avoid interpreting a quieter monitoring display as an improved hardware condition, and keep drive health diagnosis within the separately reviewed storage process.\n\n## Verification and evidence\n\nProposed verification: inspect the selected disk identities and effective standby and APM settings against the plan. During the approved idle and access periods, retain the actual temperature observations and timestamps without supplying invented readings for gaps. Compare the harmless workload results with the owner’s written acceptance criteria.\n\nReview the configured population again after any bulk edit and account for every selected device. Retain actual power measurements only if an appropriate separate measurement plan was performed. Have the storage and monitoring owners accept the observed tradeoff together, leaving unexplained gaps or device behavior open instead of prescribing a universal standby value.\n\n## Official references\n\n- [TrueNAS — Disks](https://www.truenas.com/docs/scale/25.10/scaleuireference/storage/disksscreen/) — official product documentation; confirm the installed release and configuration.\n\nSource review completed October 30, 2026. Recheck the official documentation and deployment-specific applicability before a production change." }, "json_ld": { "@context": "https://schema.org", "@graph": [ { "@type": "Organization", "@id": "https://dsesecurity.com/#organization", "name": "Detection Systems & Engineering", "alternateName": "DSE Security", "url": "https://dsesecurity.com/", "logo": { "@type": "ImageObject", "url": "https://update.dsesecurity.com/assets/dse-logo-20260812.png?v=1.8.20" } }, { "@type": "Organization", "@id": "https://update.dsesecurity.com/#editorial-team", "name": "DSE Security Editorial Team", "url": "https://update.dsesecurity.com/", "parentOrganization": { "@id": "https://dsesecurity.com/#organization" } }, { "@type": "WebSite", "@id": "https://update.dsesecurity.com/#website", "name": "DSE Updates", "alternateName": "DSE Security Knowledge Hub", "url": "https://update.dsesecurity.com/", "inLanguage": "en-US", "publisher": { "@id": "https://dsesecurity.com/#organization" }, "potentialAction": { "@type": "SearchAction", "target": { "@type": "EntryPoint", "urlTemplate": "https://update.dsesecurity.com/?q={search_term_string}" }, "query-input": "required name=search_term_string" } }, { "@type": "WebPage", "@id": "https://update.dsesecurity.com/updates/account-for-the-truenas-temperature-gap-before-allowing-disk-standby/", "url": "https://update.dsesecurity.com/updates/account-for-the-truenas-temperature-gap-before-allowing-disk-standby/", "isPartOf": { "@id": "https://update.dsesecurity.com/#website" }, "lastReviewed": "2026-10-30" }, { "@type": "BreadcrumbList", "@id": "https://update.dsesecurity.com/updates/account-for-the-truenas-temperature-gap-before-allowing-disk-standby/#breadcrumbs", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "DSE Updates", "item": "https://update.dsesecurity.com/" }, { "@type": "ListItem", "position": 2, "name": "Business Continuity", "item": "https://update.dsesecurity.com/topic/business-continuity/" }, { "@type": "ListItem", "position": 3, "name": "Account for the TrueNAS temperature gap before allowing disk standby", "item": "https://update.dsesecurity.com/updates/account-for-the-truenas-temperature-gap-before-allowing-disk-standby/" } ] }, { "@type": [ "Article", "TechArticle" ], "@id": "https://update.dsesecurity.com/updates/account-for-the-truenas-temperature-gap-before-allowing-disk-standby/#article", "identifier": "https://update.dsesecurity.com/updates/account-for-the-truenas-temperature-gap-before-allowing-disk-standby/", "url": "https://update.dsesecurity.com/updates/account-for-the-truenas-temperature-gap-before-allowing-disk-standby/", "headline": "Account for the TrueNAS temperature gap before allowing disk standby", "description": "Review the documented loss of temperature monitoring during standby separately from APM idle-power behavior.", "abstract": "Review the documented loss of temperature monitoring during standby separately from APM idle-power behavior.", "articleBody": "Bottom line: Include the temperature-observation gap in the disk power decision. Keep standby timing, APM idle behavior and the storage owner’s monitoring requirements as separate entries.\nSource fact: what the authority says\nThe TrueNAS 25.10 Disks reference defines HDD Standby as an inactivity interval and uses Always On as its default. Temperature monitoring is disabled for disks in standby. The APM setting controls idle power-management behavior rather than maximum performance capability; actively accessed drives operate at full performance regardless of that setting. Bulk Edit Disks changes multiple disks together and lists the selected device names in Disks to be edited.\nWhat the source does not establish\nThis article reviews a documented power and monitoring tradeoff, not drive qualification or a guarantee of energy savings. It does not equate an absent temperature reading with a healthy disk or prescribe a universal standby interval.\nApplicability questions\n\nWhich exact disks and workloads are included in the power-policy proposal?\nWhat standby interval and APM setting are currently configured?\nWhat temperature observations does the monitoring owner require?\nWho will review gaps and the actual effect of an approved isolated trial?\n\nDSE recommendation: controlled next steps\nThe following steps are DSE recommendations based on the cited source.\nDSE recommends documenting the monitoring requirement before selecting a standby interval. Ask the storage owner to decide whether the proposed temperature-observation gap is acceptable for the named disks. Keep that decision separate from a general desire to reduce power use, and do not claim a saving without a measured comparison.\nInventory the selected device names and current settings with a second operator. Review the installed-release procedure and the edit eligibility of the actual devices before applying a bulk change. Keep different drive populations and workload requirements distinct rather than approving every disk merely because the interface offers a shared selection.\nPrepare an isolated trial with an owner-approved idle period and a harmless access workload. Record the expected monitoring observations and acceptable application behavior in advance. Treat standby timing and APM choice as separate variables so an unexplained change is not attributed to both settings without evidence.\nAgree who investigates an unexpected temperature gap or workload interruption and who can restore the prior settings. Preserve the starting device list and configuration. Avoid interpreting a quieter monitoring display as an improved hardware condition, and keep drive health diagnosis within the separately reviewed storage process.\nVerification and evidence\nProposed verification: inspect the selected disk identities and effective standby and APM settings against the plan. During the approved idle and access periods, retain the actual temperature observations and timestamps without supplying invented readings for gaps. Compare the harmless workload results with the owner’s written acceptance criteria.\nReview the configured population again after any bulk edit and account for every selected device. Retain actual power measurements only if an appropriate separate measurement plan was performed. Have the storage and monitoring owners accept the observed tradeoff together, leaving unexplained gaps or device behavior open instead of prescribing a universal standby value.\nOfficial references\n\nTrueNAS — Disks — official product documentation; confirm the installed release and configuration.\n\nSource review completed October 30, 2026. Recheck the official documentation and deployment-specific applicability before a production change.", "datePublished": "2026-10-30T06:04:37+00:00", "dateModified": "2026-10-30T06:05:14+00:00", "mainEntityOfPage": { "@id": "https://update.dsesecurity.com/updates/account-for-the-truenas-temperature-gap-before-allowing-disk-standby/" }, "inLanguage": "en-US", "isAccessibleForFree": true, "author": { "@type": "Organization", "name": "DSE Security Editorial Team", "url": "https://update.dsesecurity.com/#editorial-team" }, "publisher": { "@id": "https://dsesecurity.com/#organization" }, "image": { "@type": "ImageObject", "@id": "https://update.dsesecurity.com/updates/account-for-the-truenas-temperature-gap-before-allowing-disk-standby/#primaryimage", "url": "https://update.dsesecurity.com/assets/editorial/network-infrastructure-social-v2.jpg?v=1.8.20", "contentUrl": "https://update.dsesecurity.com/assets/editorial/network-infrastructure-social-v2.jpg?v=1.8.20", "width": 1200, "height": 630, "caption": "Account for the TrueNAS temperature gap before allowing disk standby" }, "articleSection": [ "Business Continuity", "Networks & Infrastructure" ], "keywords": [ "Business Continuity", "Networks & Infrastructure", "Guide", "Advisory priority" ], "genre": "Guide", "about": [ { "@type": "Thing", "name": "Business Continuity", "url": "https://update.dsesecurity.com/topic/business-continuity/" }, { "@type": "Thing", "name": "Networks & Infrastructure", "url": "https://update.dsesecurity.com/topic/networks-infrastructure/" } ], "wordCount": 524, "timeRequired": "PT3M", "publishingPrinciples": "https://update.dsesecurity.com/updates/dse-updates-editorial-methodology/", "usageInfo": "https://update.dsesecurity.com/usage/", "copyrightHolder": { "@id": "https://dsesecurity.com/#organization" }, "copyrightNotice": "Copyright © 2026 Detection Systems & Engineering. All rights reserved.", "citation": { "@type": "CreativeWork", "name": "TrueNAS — Disks", "url": "https://www.truenas.com/docs/scale/25.10/scaleuireference/storage/disksscreen/" } } ] } }