docs: add AKS v20261025 release notes by dyu1208 · Pull Request #6043 · Azure/AKS

Dian Yu (dyu1208) · 2026-10-23T21:25:24Z

Summary

Draft the AKS v20261025 release notes.

Add the ## Release Notes - 2026-10-25 section to CHANGELOG.md: an announcement, Kubernetes versions, features, preview features, behavioral changes, bug fixes, and component updates.
Add 14 node image release-note files under vhd-notes/, copied verbatim from AgentBaker. The section links the latest image for each family.

The section was drafted from the customer-facing aks-rp PRs in the release, then edited to the release-note format. Where a PR description had release-note text from its Feature PM, that text is used.

Validation

Each vhd-notes/ file matches its AgentBaker source byte for byte, and every vhd-notes/ link in the new section resolves to a file in this PR.
Each new upstream release tag exists, and each new learn.microsoft.com link returns HTTP 200.
The new section passes markdownlint.
No lines from earlier releases are changed.

Add the 2026-10-23 release section to CHANGELOG.md and the node image release notes it links, copied from AgentBaker. Co-Authored-By: Claude <noreply@anthropic.com>

Copilot

🔵 Needs a closer look

Regional rollout, feature availability, and disruptive migration claims require release-owner confirmation against the underlying release changes.

No open issues 🎉

What changed in this PR

Adds the AKS v20261023 release notes to the repository’s release history, with customer-facing changes and supporting node image inventories.

Changes:

Documents Kubernetes availability, features, previews, behavioral changes, and bug fixes.
Lists component updates and links the latest node image notes for each family.
Adds build details and component inventories for node images.

File	Description
`vhd-notes/AzureLinuxv3/202610.16.1.txt`	Adds Azure Linux 3 build inventory for October 16.
`vhd-notes/AzureLinuxv3/202610.08.0.txt`	Adds Azure Linux 3 build inventory for October 8.
`vhd-notes/AzureLinuxv3/202610.03.0.txt`	Adds Azure Linux 3 build inventory for October 3.
`vhd-notes/AzureContainerLinuxv3/202610.16.1.txt`	Adds Azure Container Linux build details for October 16.
`vhd-notes/AzureContainerLinuxv3/202610.08.0.txt`	Adds Azure Container Linux build details for October 8.
`vhd-notes/AzureContainerLinuxv3/202610.03.0.txt`	Adds Azure Container Linux build details for October 3.
`vhd-notes/AKSWindows/2022/20348.5761.261015.txt`	Adds Windows Server 2022 updates and image inventory.
`CHANGELOG.md`	Adds the October 23 release summary and node image links.

_{Review effort: Balanced}

KAARTHIKEYAN SUBRAMANIAN (kaarthis)

PTAL few announcements and corrections

KAARTHIKEYAN SUBRAMANIAN (kaarthis) · 2026-10-23T23:24:47Z

+
+#### Behavioral changes
+
+* [Node Auto Provisioning (NAP)](https://learn.microsoft.com/azure/aks/node-autoprovision) will now have the following changes:


Feel like all the NAP announcements should be lumped together in one NAP mega bullet / header and sub points for easier consumption. Wilson (@wdarko1) Dian Yu (@dyu1208)

KAARTHIKEYAN SUBRAMANIAN (kaarthis) · 2026-10-23T23:27:28Z

+#### Behavioral changes
+
+* [Node Auto Provisioning (NAP)](https://learn.microsoft.com/azure/aks/node-autoprovision) will now have the following changes:
+  * VM SKUs within about six months of retirement are no longer selected for new nodes.


Not very clear what is the value prop of this and Link ?

I think the value prop is stopping to use almost retired SKUs from being considered by our automatic selection but some doc mention (even if just in our FAQ) is not a bad idea

Co-authored-by: Ally Ford <37671069+allyford@users.noreply.github.com>

Copilot

🔵 Needs a closer look

A release owner should confirm feature availability, regional rollout, and disruptive migration guidance against the originating aks-rp changes before publication.

No open issues 🎉

_{Review effort: Balanced}

Copilot

🟡 Changes recommended

The published release identifier conflicts with the PR’s stated target and needs confirmation before publication.

1 open issue

Reconcile inconsistent release identifiers · New

_{Review effort: Balanced}

Copilot

🔵 Needs a closer look

The release identifier remains inconsistent between the changelog (v20261025) and the stated PR target (v20261023).

No open issues 🎉

2 previously missed issues

In code that hasn't changed since last review

Correct grammatically incorrect end-of-life wording

CHANGELOG.md:20

“Are going soon end of life” is grammatically incorrect and obscures the support deadline. Use “will reach end of life in November 2026.”

Remove invalid nested Markdown link

CHANGELOG.md:54

This wraps an existing Markdown link in another link. CommonMark does not allow nested links, so the extra brackets and destination appear as literal text alongside the working inner link. Remove the outer wrapper so the published note displays only the linked product name.

1 resolved since last review

Reconcile inconsistent release identifiers

_{Review effort: Balanced}

Jorge Palma (palma21) · 2026-10-26T20:04:39Z

+  * When `osDiskSizeGB` isn't specified, the default OS disk size now matches AKS behavior, including SKU-appropriate ephemeral disk sizing where supported.
+  * Before choosing an ephemeral disk, NAP now checks eligible disk placements and accounts for Trusted Launch storage needs, preventing failed provisioning.
+  * NAP now respects external load balancer exclusions when deciding whether to add nodes to external load balancers.
+* [Network isolated clusters](https://learn.microsoft.com/azure/aks/concepts-network-isolated) will now automatically purge stale AKS-cached images from the managed Azure Container Registry, reclaiming registry storage in public Azure regions.


This on the docs KAARTHIKEYAN SUBRAMANIAN (@kaarthis) ?

Jorge Palma (palma21) · 2026-10-26T20:05:54Z

+* [Istio-based service mesh add-on](https://learn.microsoft.com/azure/aks/istio-about) will now intercept both IPv4 and IPv6 workload traffic on dual-stack clusters. Restart existing workloads after the add-on update to apply the new proxy configuration.
+* [Application Routing Gateway API](https://learn.microsoft.com/azure/aks/app-routing-gateway-api) controller will now run on the managed system node pool in AKS Automatic clusters, improving isolation between the control plane and data plane.
+* [[AKS Automatic](https://learn.microsoft.com/azure/aks/intro-aks-automatic)](https://learn.microsoft.com/azure/aks/intro-aks-automatic) clusters on Kubernetes 1.36+ now exclude protected system namespaces from customer mutating admission configurations to preserve the AKS Automatic security boundary: customer webhooks and policies can still mutate customer workloads, but they can’t mutate AKS-managed system workloads.
+* [Platform-managed keys for etcd encryption](https://learn.microsoft.com/azure/aks/kms-data-encryption?pivots=pmk) will now be enabled by default for new clusters on Kubernetes 1.37 and later, unless infrastructure encryption is explicitly configured.


We have this in all places where we must? Thinking not just the feature doc but the security best practices and concepts as well as the secure baselines, etc. This should be mentioned / included, and might even change any recommendation? KAARTHIKEYAN SUBRAMANIAN (@kaarthis)

docs: add AKS v20261023 release notes

d71c3e8

Add the 2026-10-23 release section to CHANGELOG.md and the node image release notes it links, copied from AgentBaker. Co-Authored-By: Claude <noreply@anthropic.com>

Dian Yu (dyu1208) marked this pull request as ready for review October 23, 2026 21:35

Dian Yu (dyu1208) requested review from a team and Kaysie Yu (kaysieyu) October 23, 2026 21:35

Dian Yu (dyu1208) requested review from a team and Jorge Palma (palma21) as code owners October 23, 2026 21:35

Dian Yu (dyu1208) requested review from Robbie Zhang (robbiezhang) and a balanced review from Copilot October 23, 2026 21:35

Copilot started reviewing on behalf of Dian Yu (dyu1208) October 23, 2026 21:35

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Copilot AI reviewed Oct 23, 2026

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Amanda Wang (wangyira) reviewed Oct 23, 2026

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