Infrastructure as Code - is software that configures and operates basic infrastructure - servers, networking, kubernetes platform. Because this code manage very basic layer of system, it is applied manually by DevOps Engineer. Infrastructure as Code - does not have the “operate” step, it modify infrastructure and then this infrastructure operates on cloud independently. Monitoring step use the common monitoring and alerting tools to monitor cloud infrastructure and notify about incidents.
This is a companion discussion topic for the original entry at https://docs.cloudposse.com/devops-methodology/software-lifecycle/infrastructure-as-code/