Ansible vs Terraform – What is the Diference ? (Pros and Cons)
Every tech organization or a rising startup wants to automate its IT infrastructure and application. Two of the most important DevOps tools that help in achieving the feat are Ansible and Terraform. Both the tools have ease of deployment and redeployment on different infrastructures. They are also the tools that help in automating configurations.
Ansible is a configuration management tool that uses LaaC to help in automating system configuration and management. Terraform allows you to position infrastructure as a code (LaaC) that supports understanding the infrastructure or readability and shifting and lifting deployments.
Let us get into a detailed understanding of both these tools before diving into their comparative analysis.
What is Ansible?
Ansible is a software provisioning and application deployment system that uses infrastructure as a code. It is an open-sourced configuration management tool. It has its own declarative language system to explain system configuration.
Ansible is generally used to deploy/install and manage software on existing server instances. The tool allows you to perform ad hoc commands and procedural-style configuration simultaneously with high-level declarative-style configurations.
Some tasks of the configuration management tool Ansible include initialization of services, managing and deploying installation packages, and running-config files or scripts on the server. Ansible uses LaaC only for configuration management on deployed servers.
Ansible is the perfect tool for traditional configuration management. It is not suitable for orchestration services in large enterprises with interconnected systems.
How does Ansible work?
Ansible is agentless. It is thus easy to manage large deployments across enterprises using Windows PowerShell or SSH to perform any task. Ansible is a hybrid of declarative and procedural patterns. It is not entirely declarative.
Ansible using JSON installs various Python modules on the target. These modules are nothing but simple directives that run on the target. Once their job is done, the models are executed and removed. Thus ensuring a strategy that prevents misuse of resources on target. Python needs to be mandatorily installed on both target nodes and control nodes.
Ansible management node performs as the controlling node that controls the entire execution of the playbook. This node is the place where installations are run. The inventory file provides the host list where modules need to be run. To install the product on the host machine, the management node makes SSH connections to execute the modules. Modules are removed once they are installed in the system.
What are the features of Ansible?
- Ansible is used for configuration management that follows procedural paradigms
- Ansible follows unaltered behavior that helps it to place nodes in the same state at all times
- Ansible works with infrastructure platforms like cloud networks, bare metal, and hypervisors
- Ansible uses infrastructure as code system configuration for all infrastructures
- Ansible allows to rapidly and easily install multi-tier apps while being agentless
- Ansible allows the code to be interrupted and re-entered without any conflicts with other citations
Pros and Cons of Ansible
Pros:
- Simple and easy to learn – The most lauded attribute of Ansible is its simplicity. It is supported by easy and clear documentation that makes developers learn the workflow and logic of Ansible in a very short time.
- Written in Python – Ansible was written in Python. It is a language that is more common for scripting and administration tasks. Also, Python libraries are by default present on most Linux distributions.
- Agentless – Ansible is agentless. It manages nodes with standard SSH, which is a Python implementation of SSH2. The tool doesn’t require any agents to be installed to manage remote systems.
- YAML-based Playbooks – Ansible configuration files are coded in YAML, which is a better fit than other formats like JSON for configuration management and automation purposes.
- Ansible Galaxy – The galaxy serves as a central repository for sharing, reusing, and finding Ansible content.
Cons:
- No concept of State – Unlike other automation tools, Ansible has no concept of state. It just executes a series of tasks, stopping when it fails, finishes, or encounters a problem.
- Lacks user interface – What started off as a command-line only tool made its first progress as a UI with AWX, which eventually evolved into Ansible Tower, a web management UI. However, Ansible Tower is still short of what a command-line interface can do.
- Budding Windows support – Ansible supports both Linux/Unix and Windows nodes. Ansible is still early in its efforts to support Windows completely.
- Minimal enterprise support – Ansible has less experience working with large enterprises. Although Ansible’s Enterprise Tower and Premium Tower are targeted at medium to large enterprises, they offer only extended support.
What is Terraform?
Terraform, developed by HashiCorp, is an open-source infrastructure as a code. It is a code solution that is used for versioning, building, and changing infrastructure effectively and securely. The code is written in HashiCorp configuration language and describes the infrastructure as declarative by nature.
Terraform helps to manage the state of the network and develop the scale of services. It is primarily used in the software-defined networking domain and the data centers. The tool does not install nor does it manage software on existing devices. Rather, it creates, changes, and destroys other cloud services.
Starbucks, Uber, Slack, Twitch are some of the big brands using Terraform. It can also be integrated with Microsoft Azure, Google Compute Engine, and Heroku, etc. With support from more than 200 infrastructure providers, including SaaS, public, and private cloud providers, Terraform is a very popular utility in the world of DevOps.
How does Terraform work?
Terraform has two main working components. They are:
- Terraform Core
- Providers
Terraform directly explains the end state of the system without describing the process of how to get there. The tool is of declarative nature. It works abstractly to define what services and resources should be created. If users need to access the final state, they would have to install and configure the application using various tools and scripts.
Terraform Core requires two input sources to do the job. The first source is Terraform configuration that the user configures by defining what needs to be provided and created. The second source is a state that posses information about the infrastructure. Thus, Terraform Core takes all the inputs and chalks out plans to follow to get the desired result.
The other important component is Providers as in cloud providers like Azure, GCP, AWS, or any other infrastructure as a cloud platform. Terraform helps to create infrastructure on multiple levels. It also supports infrastructure orchestration, which means plans are to be executed in an orderly manner with the help of resource graphs.
Terraform is useful in automating processes that provide resources and are helpful in the migration to the cloud. The multi-threaded feature of Terraform allows parallel computing that is useful for creating a set of resources simultaneously.
What are the features of Terraform?
- Terraform is an excellent tool for displaying the resulting model in a graphical format
- Terraform is an infrastructure as a coding platform that is declarative. It makes the deployments easy and quick.
- Terraform is a one of a kind tool that helps to build infrastructure from scratch, be it multi-cloud, public or private
- Terraform helps to manage simultaneous environments, thus making it an excellent choice for validating bug fixes, testing, and formal acceptance
- Terraform is a modular code that encourages reusability, consistency, and collaboration. It can be easily tweaked for specific purposes.
- Terraform manages multiple clouds to speed up fault tolerance
Ansible Vs Terraform - Key Differences
Ansible vs Terraform: Which one is better?
Every tool is unique in its own way.
Ansible has better security and ACL functionality. The tool adjusts itself beautifully with the traditional automation frameworks. It helps to code rapidly and is simple in operation. It is considered to be a mature tool. However, it lacks behind in orchestration services, interconnected applications, and logical dependencies.
Terraform is very user-friendly and offers excellent scheduling capabilities. It integrates with Docker very well, which in turn handles configuration management a little better than Terraform. There is however no evidence of the way the target devices are brought to their final state. At times, this makes the final configuration unnecessary.
What you choose depends on the job at hand. If you are looking to gain control of your devices and find different ways to deploy underlying services, you need Ansible. But if the requirement is for provisioning software within the cloud, use Terraform.
Both the tools are sure to provide comprehensive services in the future.
Final Thoughts
While Terraform has the support of more than 200 providers in provisioning infrastructure across multiple clouds, which is its core strength, Ansible is good at both configuration management and provisioning. Hence, a combination of Ansible for configuration management and Terraform for orchestration services is a pretty good model to go by.
Whether you pick a standalone tool or a combination of both the tools, it should be based on the job requirement and the best possible outcome.
