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

[zachary-bailey]

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[azure-client-tools-bot-prd]

❌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

[azure-pipelines]

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

[azure-pipelines]

Azure Pipelines successfully started running 2 pipeline(s).

[zachary-bailey]

@FumingZhang will do, I converted this to a draft though because we are going to wait to merge until other changes have been merged. Thanks for the help so far!

cc: @Sebby37

[FumingZhang]

@zachary-bailey are you still working on this change?

[cameronmeissner]

@FumingZhang yeah we're still working on it, we're waiting for functionality to be available in RP (ETA within the next week) before taking this out of draft, in the meantime we're working on creating a private bug bash container using AZCLI handbook