Hi @Maulin Shah (Crest Data Systems Private Lim)
There could be several reasons why the automatic OS upgrade is not working as expected. Here are a few things you can check and let me know.
Check if the VMSS is configured to use the latest version of the image in the Shared Image Gallery. You can do this by checking the "latest" tag in the image definition in the Shared Image Gallery.
Check if the VMSS is configured to use the correct image definition in the Shared Image Gallery. You can do this by checking the "imageReference" property in the VMSS definition.
Check if the VMSS is configured to use the correct update policy. You can do this by checking the "upgradePolicy" property in the VMSS definition.
Check if the VMSS instances are healthy and able to receive the update. You can do this by checking the health status of the VMSS instances in the Azure portal.
Check if there are any errors or warnings in the VMSS logs or in the Azure Activity Log. You can do this by checking the logs for the VMSS instances and the Azure Activity Log in the Azure portal.
If you have checked all the above and are still experiencing issues, you may want to contact Microsoft support for further assistance. They can help you troubleshoot the issue and provide guidance on how to resolve it.
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