[AKS] Relax validation so apiserver_subnet_id is not required during non-HOBO to HOBO conversion

[reneeli123]

🤖 PR Validation — ️✔️ All clear

Breaking Changes
️✔️ None

---

This checklist is used to make sure that common guidelines for a pull request are followed.

Related command

az aks update: Relax the bring-your-own VNet subnet validation for converting non-HOBO to HOBO Automatic cluster. --apiserver-subnet-id is no longer required, and --system-node-subnet-id can be supplied on its own; omitted subnets keep their current networking. --enable-hosted-system is still required to request the conversion, and --node-subnet-id still requires --system-node-subnet-id.

General Guidelines

• Have you run azdev style <YOUR_EXT> locally? (pip install azdev required)
• Have you run python scripts/ci/test_index.py -q locally? (pip install azdev required)
• My extension version conforms to the Extension version schema

For new extensions:

• My extension description/summary conforms to the Extension Summary Guidelines.

About Extension Publish

There is a pipeline to automatically build, upload and publish extension wheels.
Once your pull request is merged into main branch, a new pull request will be created to update src/index.json automatically.
You only need to update the version information in file setup.py and historical information in file HISTORY.rst in your PR but do not modify src/index.json.

[azure-client-tools-bot-prd]

Hi reneeli123,
Please write the description of changes which can be perceived by customers into HISTORY.rst.
If you want to release a new extension version, please update the version in pyproject.toml (or setup.py, if the extension has not migrated yet) as well.

[azure-pipelines]

Azure Pipelines:
There may be pipelines that require an authorized user to comment /azp run to run.

[Copilot]

Pull request overview

This PR updates the aks-preview extension’s az aks update hosted-system (HOBO) conversion flow to relax bring-your-own VNet subnet validation: --apiserver-subnet-id is no longer required during non-HOBO → HOBO conversion, and --enable-hosted-system must be specified explicitly to request the conversion.

Changes:

• Adjust hosted-system enablement and BYO subnet cross-validation logic for UPDATE vs CREATE flows.
• Update help text/examples to reflect the new conversion requirements and optional subnet behavior.
• Update unit tests, bump extension version, and add a changelog entry for the change.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/aks-preview/setup.py	Bumps extension version to 22.0.0b2.
src/aks-preview/HISTORY.rst	Adds release notes for 22.0.0b2 describing the relaxed validation.
src/aks-preview/azext_aks_preview/tests/latest/test_managed_cluster_decorator.py	Updates/expands tests to cover explicit conversion request and optional subnet combinations.
src/aks-preview/azext_aks_preview/managed_cluster_decorator.py	Updates conversion enablement rules and BYO subnet validation behavior for update-mode conversions.
src/aks-preview/azext_aks_preview/_help.py	Updates parameter descriptions and examples for the new subnet/conversion semantics.

Suppressed comments (1)

src/aks-preview/azext_aks_preview/managed_cluster_decorator.py:4376

• Similar to the prior message, this SKU error message implies both subnet flags are present ("--system-node-subnet-id" and "--node-subnet-id"). Since the UPDATE validation is triggered when either subnet flag is used, consider wording the message to reflect that either flag is only supported for Automatic SKU clusters.

            if self.get_sku_name() != CONST_MANAGED_CLUSTER_SKU_NAME_AUTOMATIC:
                raise RequiredArgumentMissingError(
                    '"--system-node-subnet-id" and "--node-subnet-id" are only supported on '
                    "clusters with the Automatic SKU."
                )

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.

[Aditya Pujara (a0x1ab)]

/azp run

[azure-pipelines]

Azure Pipelines:
Successfully started running 2 pipeline(s).

[Aditya Pujara (a0x1ab)]

/azp run

[azure-pipelines]

Azure Pipelines:
Successfully started running 2 pipeline(s).

[Aditya Pujara (a0x1ab)]

/azp run

[azure-pipelines]

Azure Pipelines:
Successfully started running 2 pipeline(s).

[Aditya Pujara (a0x1ab)]

/azp run

[azure-pipelines]

Azure Pipelines:
Successfully started running 2 pipeline(s).

[Azure CLI Bot (azclibot)]

[Release] Update index.json for extension [ aks-preview-22.0.0b3 ] : https://dev.azure.com/msazure/One/_build/results?buildId=177571026&view=results