I have a sitecore application deployed to azure webapp. It is exposed to end users through the application gateway.
There is a staging slot on the webapp and during the deployment we deploy to the staging slot, do final testing there (using azurewebsites domain) and the perform the slot swap - all the common stuff.
What is bothering us at the moment is that after the slot swap Application Gateway health probes mark the backend (with only 1 target) as unhealthy and the app goes down for about 3-5 minutes (with the "usual" 502 gateway error). We would like to avoid this, as the slot swap should not affect the performance that much.
What are the correct settings of the App Gateway to avoid this issue? Set health probe timeout to something ridiculous like 20 minutes?