How do warm up work on Deployment slot in Azure App Service

Question

I do have an Azure App Service API app which is developed and deployed on a deployment slot named Testing. I have another deployment slot named Production. The auto swap is enabled for the Testing slot.

Do I need to include applicationInitialization configuration element in web.config to ensure that scripts run and resources are available before a swap operation occurs?

Answer 1

Hello @Rachel Tan , Welcome to Microsoft QnA. Thank you for the question.

Once the slot starts getting prepared for the swap, a warm up request is made to the root directory of the site on every instance. However if that is not enough , then may make request to all the important routes in the application or prepopulate in-memory cache. Yes, application initialization configuration would help in that case: iis-80-application-initialization

deploy-staging-slots- Specify custom warm-up

Please refer to deploy-staging-slots to understand what happens during a swap.

Please let me know if this helps.