I just scaled down an Umbraco site running in an Azure app service from S2 to S1 which caused the server to restart.
This was a production instance so we need to know if this is what is supposed to happen.
I've been unable to find out whether this is the correct behaviour for an app service, or whether this is something to do with my app/Umbraco.
I looked in Scale up an app in Azure (this was the only seemingly relevant doc I could find) but haven't been able to find out.
Can anyone help?
Vertical scaling (changing the plan S1 -> S2 -> S1) often requires making the system temporarily unavailable while it is being redeployed.
For best availability consider making your application horizontally scalable. That way it will always be running on some instances when new ones are spawned, or old ones are removed.
Please see this link for some additional information regarding scaling.
Also, in the background, an App Service plan is just a VM running IIS, therefor check out this link also for when VMs might experience downtime when being scaled vertically.