App Service Plan

• It's a machine where the web apps will run
• One app service plan can have multiple web apps
• One app service plan can run multiple runtime stack, but only one OS

• One app service plan can run apps from the same region only

• SKU and sizes

• Free (F): 1 GB disk. 10 apps. 60 min / day

• Shared (D): 1 GB disk. 100 apps. 240 min /day
• Basic (B): 10 GB. Up to 3 instances
• Standard (S): 50 GB. Up to 10 instances. Autoscale
• Premium (P): 250 GB. Up to 30 instances. Autoscale
• Isolated: 1 TB. Up to 100 instances. Autoscale

• App Service Linux

• You are billed based on the consumpting of the app service plan, not the web app itself

App Service Environment (ASEs)

• When your app is assigned exclusively to a single service plan
• Useful for huge applications (E.g., e-commerce portal)

Autoscaling

• Requires the standard app service plan

• For inferior app service plans, only manual scaling is allowed

• Scale out: increase number of instances

• Scale in: decrease number of instances
• Scale up: increate size of instances

• Scale down: decrease size of instances

• Conditions

• Based on metrics of the app service plan
  • CPU percentage
  • Memory percentage
• Based on metrics of other azure resources
• Cool down period: time after a scale rule has been triggered in which no actions can be triggered again
• Maximum and minimum instances: to avoid DDoS attacks