Allow Virtual Machine Scale Sets to have both Rolling upgrade mode and Automatic OS Upgrade

[MarcDenman]

Currently when creating/updating VMSS through the AzureRM provider, you are unable to use the Rolling upgrade mode and have Automatic OS Policy enabled. You receive the following error:

an automatic_os_upgrade_policy block cannot be specified when upgrade_mode is not set to Automatic"

After looking through the VMSS documentation, I can't see any technical reason for this and I have managed to create/update a VMSS through the Azure Portal with both the Rolling upgrade mode and Automatic OS Upgrade enabled with the resulting ARM template below.

Looking at the VMSS resources, I think it is changing a couple checks to allow Rolling to be specified and with no further changes needed. I have tested by building locally and running locally and it has worked as expected

"properties": {
                "singlePlacementGroup": true,
                "upgradePolicy": {
                    "mode": "Rolling",
                    "rollingUpgradePolicy": {
                        "maxBatchInstancePercent": 20,
                        "maxUnhealthyInstancePercent": 100,
                        "maxUnhealthyUpgradedInstancePercent": 20,
                        "pauseTimeBetweenBatches": "PT60S",
                        "enableCrossZoneUpgrade": false,
                        "prioritizeUnhealthyInstances": false
                    },
                    "automaticOSUpgradePolicy": {
                        "enableAutomaticOSUpgrade": true,
                        "useRollingUpgradePolicy": false,
                        "disableAutomaticRollback": false
                    }
                },
                .....

#13745

[katbyte]

Thanks for this @MarcDenman - could you add some tests to verify/ensure this continues to work? thanks!

[katbyte]

thanks @MarcDenman - LGTM 👾

[github-actions]

This functionality has been released in v3.30.0 of the Terraform Provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!

[github-actions]

I'm going to lock this pull request because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active contributions.
If you have found a problem that seems related to this change, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.