DevOps Classroom notes 21/Dec/2023

Terraform contd

Terraform functions to identify ip ranges

• using cidr subnet Refer Here
  
• Refer Here for the changes done to accomodate in aws ntier
• Lets try to apply what we have learnt so far for ntier in azure.
• Refer Here for the changes

Terraform plan

• Terraform whenever applied will check for the difference in desired state and actual state.
• This becomes a plan for terraform which gets execute
• First time execution: (No resources are exist in provider)
  
• Next Time Execution
  
• Terraform apply = Terraform plan out + apply the plan

Terraform state

• When we execute apply in terraform
  • checks for a state file (by default in same folder)
    • if exists
      • tries to get the latest state from provider (refresh the state)
      • if latest state is exactly equal to previous generated then terraform has nothing to do
      • if there is a difference
        • creates a backup for state
        • executes a new plan
    • else:
      • creates a plan and executes the plan
      • result of what was created will be stored in tfstate file