`--bootstrap-artifact-source Cache` is required when updating ACR for AKS network isolated cluster

[bingosummer]

Describe the bug

When updating your ACR ID using "az aks update" for the feature network isolated cluster, both --bootstrap-artifact-source Cache and --bootstrap-container-registry-resource-id <New BYO ACR resource ID> need to be specified.
If --bootstrap-artifact-source Cache is not specified, the request will be ignored and the ACR ID won't be updated to the cluster.

Ref: https://learn.microsoft.com/en-us/azure/aks/network-isolated?pivots=byo-acr#update-your-acr-id

Related command

az aks update --resource-group ${RESOURCE_GROUP} --name ${AKS_NAME} --bootstrap-artifact-source Cache --bootstrap-container-registry-resource-id

Errors

No error raised. The request of updating ACR is ignored.

Issue script & Debug output

N/A

Expected behavior

Specify both --bootstrap-artifact-source Cache and --bootstrap-container-registry-resource-id <New BYO ACR resource ID>

Environment Summary

$ az --version
azure-cli 2.71.0

core 2.71.0
telemetry 1.1.0

Extensions:
azure-firewall 1.2.2
kusto 0.5.0
quota 1.0.0
virtual-wan 1.0.1

Dependencies:
msal 1.31.2b1
azure-mgmt-resource 23.1.1

Python location '/opt/az/bin/python3'
Config directory '/home/binxi/.azure'
Extensions directory '/home/binxi/.azure/cliextensions'

Python (Linux) 3.12.8 (main, Mar 25 2025, 10:55:59) [GCC 9.4.0]

Legal docs and information: aka.ms/AzureCliLegal

Your CLI is up-to-date.

Additional context

No response

[yonzhan]

Thank you for opening this issue, we will look into it.