How to Setup and Use App Service Deployment Slots 

Azure App Service offers a feature called Deployment Slots for which allows you to have multiple environments for your Web App each with their own separate host names.
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This is useful when you want to first deploy changes to a staging environment, then once you are comfortable the Web App is performing as expected you can swap the staging environment with the production environment.
The benefits from this is that:
It enables you to verify the application is working as expected in a production like environment
It eliminates down time in production when deploying changes
It enables you to rollback if there is a problem with the production environment following the deployment
• How to Deploy an App S...