github.com/Kevinklinger/open_terraform@v0.11.12-beta1/website/intro/vs/cloudformation.html.markdown (about) 1 --- 2 layout: "intro" 3 page_title: "Terraform vs. CloudFormation, Heat, etc." 4 sidebar_current: "vs-other-cloudformation" 5 description: |- 6 Tools like CloudFormation, Heat, etc. allow the details of an infrastructure to be codified into a configuration file. The configuration files allow the infrastructure to be elastically created, modified and destroyed. Terraform is inspired by the problems they solve. 7 --- 8 9 # Terraform vs. CloudFormation, Heat, etc. 10 11 Tools like CloudFormation, Heat, etc. allow the details of an infrastructure 12 to be codified into a configuration file. The configuration files allow 13 the infrastructure to be elastically created, modified and destroyed. Terraform 14 is inspired by the problems they solve. 15 16 Terraform similarly uses configuration files to detail the infrastructure 17 setup, but it goes further by being both cloud-agnostic and enabling 18 multiple providers and services to be combined and composed. For example, 19 Terraform can be used to orchestrate an AWS and OpenStack cluster simultaneously, 20 while enabling 3rd-party providers like Cloudflare and DNSimple to be integrated 21 to provide CDN and DNS services. This enables Terraform to represent and 22 manage the entire infrastructure with its supporting services, instead of 23 only the subset that exists within a single provider. It provides a single 24 unified syntax, instead of requiring operators to use independent and 25 non-interoperable tools for each platform and service. 26 27 Terraform also separates the planning phase from the execution phase, 28 by using the concept of an execution plan. By running `terraform plan`, 29 the current state is refreshed and the configuration is consulted to 30 generate an action plan. The plan includes all actions to be taken: 31 which resources will be created, destroyed or modified. It can be 32 inspected by operators to ensure it is exactly what is expected. Using 33 `terraform graph`, the plan can be visualized to show dependent ordering. 34 Once the plan is captured, the execution phase can be limited to only 35 the actions in the plan. Other tools combine the planning and execution 36 phases, meaning operators are forced to mentally reason about the effects 37 of a change, which quickly becomes intractable in large infrastructures. 38 Terraform lets operators apply changes with confidence, as they know exactly 39 what will happen beforehand.