[AKS] Add option Ubuntu2604 to --os-sku for az aks nodepool add and az aks nodepool update

[zachary-bailey]

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❌Azure CLI Extensions Breaking Change Test

❌aks-preview

rule	cmd_name	rule_message	suggest_message
❌ 1010 - ParaPropUpdate	aks machine add	cmd aks machine add update parameter spot_max_price: updated property default from nan to nan	please change property default from nan to nan for parameter spot_max_price of cmd aks machine add
❌ 1010 - ParaPropUpdate	aks nodepool add	cmd aks nodepool add update parameter spot_max_price: updated property default from nan to nan	please change property default from nan to nan for parameter spot_max_price of cmd aks nodepool add
⚠️ 1010 - ParaPropUpdate	aks create	cmd aks create update parameter os_sku: updated property choices from ['AzureContainerLinux', 'AzureLinux', 'AzureLinux3', 'AzureLinux3OSGuard', 'AzureLinuxOSGuard', 'CBLMariner', 'Flatcar', 'Mariner', 'Ubuntu', 'Ubuntu2204', 'Ubuntu2404'] to ['AzureContainerLinux', 'AzureLinux', 'AzureLinux3', 'AzureLinux3OSGuard', 'AzureLinuxOSGuard', 'CBLMariner', 'Flatcar', 'Mariner', 'Ubuntu', 'Ubuntu2204', 'Ubuntu2404', 'Ubuntu2604']
⚠️ 1010 - ParaPropUpdate	aks machine add	cmd aks machine add update parameter os_sku: updated property choices from ['AzureContainerLinux', 'AzureLinux', 'AzureLinux3', 'AzureLinux3OSGuard', 'AzureLinuxOSGuard', 'CBLMariner', 'Flatcar', 'Mariner', 'Ubuntu', 'Ubuntu2204', 'Ubuntu2404', 'Windows2019', 'Windows2022', 'Windows2025', 'WindowsAnnual'] to ['AzureContainerLinux', 'AzureLinux', 'AzureLinux3', 'AzureLinux3OSGuard', 'AzureLinuxOSGuard', 'CBLMariner', 'Flatcar', 'Mariner', 'Ubuntu', 'Ubuntu2204', 'Ubuntu2404', 'Ubuntu2604', 'Windows2019', 'Windows2022', 'Windows2025', 'WindowsAnnual']
⚠️ 1010 - ParaPropUpdate	aks nodepool add	cmd aks nodepool add update parameter os_sku: updated property choices from ['AzureContainerLinux', 'AzureLinux', 'AzureLinux3', 'AzureLinux3OSGuard', 'AzureLinuxOSGuard', 'CBLMariner', 'Flatcar', 'Mariner', 'Ubuntu', 'Ubuntu2204', 'Ubuntu2404', 'Windows2019', 'Windows2022', 'Windows2025', 'WindowsAnnual'] to ['AzureContainerLinux', 'AzureLinux', 'AzureLinux3', 'AzureLinux3OSGuard', 'AzureLinuxOSGuard', 'CBLMariner', 'Flatcar', 'Mariner', 'Ubuntu', 'Ubuntu2204', 'Ubuntu2404', 'Ubuntu2604', 'Windows2019', 'Windows2022', 'Windows2025', 'WindowsAnnual']
⚠️ 1010 - ParaPropUpdate	aks nodepool update	cmd aks nodepool update update parameter os_sku: updated property choices from ['AzureContainerLinux', 'AzureLinux', 'AzureLinux3', 'AzureLinux3OSGuard', 'AzureLinuxOSGuard', 'Flatcar', 'Ubuntu', 'Ubuntu2204', 'Ubuntu2404'] to ['AzureContainerLinux', 'AzureLinux', 'AzureLinux3', 'AzureLinux3OSGuard', 'AzureLinuxOSGuard', 'Flatcar', 'Ubuntu', 'Ubuntu2204', 'Ubuntu2404', 'Ubuntu2604']

[Copilot]

Pull request overview

This PR updates the aks-preview extension to introduce a new OS SKU option (Ubuntu2604) for AKS node pool-related --os-sku parameters, along with the associated help text and extension versioning metadata.

Changes:

• Bump aks-preview extension version to 21.0.0b8 and add a matching HISTORY entry.
• Add Ubuntu2604 as a recognized OS SKU constant and include it in the --os-sku enum lists.
• Update command help text to list Ubuntu2604 among supported Linux OS SKUs.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/aks-preview/setup.py	Bumps the extension version to 21.0.0b8.
src/aks-preview/HISTORY.rst	Adds release notes for 21.0.0b8 describing the new Ubuntu2604 option.
src/aks-preview/azext_aks_preview/_params.py	Adds Ubuntu2604 into OS SKU enum lists used by argument definitions (including create/add/update surfaces).
src/aks-preview/azext_aks_preview/_help.py	Updates --os-sku help text to include Ubuntu2604.
src/aks-preview/azext_aks_preview/_consts.py	Introduces CONST_OS_SKU_UBUNTU2604 = "Ubuntu2604".

Comments suppressed due to low confidence (1)

src/aks-preview/azext_aks_preview/_params.py:316

• This change adds Ubuntu2604 to node_os_skus_create, which makes --os-sku Ubuntu2604 available on az aks create (see arg_type=get_enum_type(node_os_skus_create)), not just az aks nodepool add/update as stated in the PR title/HISTORY. Because node_os_skus_add is derived from node_os_skus_create, this also affects other command surfaces that reuse node_os_skus_add (e.g., aks machine add). Please either (a) update the PR title/HISTORY entry to reflect all impacted commands, or (b) restrict the enum change to only the intended command(s) if az aks create should not accept Ubuntu2604 yet.

node_os_skus_create = [
    CONST_OS_SKU_AZURELINUX,
    CONST_OS_SKU_AZURELINUX3,
    CONST_OS_SKU_FLATCAR,
    CONST_OS_SKU_UBUNTU,
    CONST_OS_SKU_CBLMARINER,
    CONST_OS_SKU_MARINER,
    CONST_OS_SKU_UBUNTU2204,
    CONST_OS_SKU_UBUNTU2404,
    CONST_OS_SKU_UBUNTU2604,
    CONST_OS_SKU_AZURELINUXOSGUARD,
    CONST_OS_SKU_AZURELINUX3OSGUARD,
    CONST_OS_SKU_AZURECONTAINERLINUX,
]
node_os_skus_add = node_os_skus_create + [

[yonzhan]

AKS

[FumingZhang]

/azp run

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Azure Pipelines successfully started running 2 pipeline(s).

[FumingZhang]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[FumingZhang]

@zachary-bailey could you rebase your feature branch onto main so the CI check passes? There’s a bug in the CI, and this is the simplest workaround.

[yanzhudd]

/azp run

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Azure Pipelines successfully started running 2 pipeline(s).