I am moving my Azure VMs over to a scale set and it's working well. I was trying not to add a custom script extension and have the scale set spin up as quick as possible but sadly I now need a few other things.
After adding the CS extension (which is also working as expected), I notice that the Scale Set property Enable Windows Automatic update (disabled) is now not working. The Windows Update service is set to manual/triggered start and windows updates are coming down to the scale set VMs.
Note: I am talking about Windows patches and not the scale set OS upgrade - which I have manual setting as using a packer custom image.
The scale set model property is still disabled (which was working fine until I added the new custom script), but I now notice the Windows Update service is now set to running and manual/trigger start and windows updates come through.
So, it appears there may be a clash between automatic updates for windows and adding a custom script. Not a huge problem as I can disable the Windows Update service again inside my custom script but can anyone explain why this might be?
Thanks