Best Infrastructure As Code Tools to use
Applications and websites like WhatsApp, Amazon, FlipKart, e-Bay etc. require large number of servers to run. Infrastructure for these applications often requires addition, updating, removing of servers according to the traffic. In earlier days, managing such large infrastructure for these applications was really complicated and effort taking since most of the time they were configured manually.
But now, infrastructure of any size or configuration can be easily managed by just writing some piece of code. Thanks to "Infrastructure as Code" tools.
In this blog, we will be discussing various IaC tools which can help us provision and manage infrastructure for our application of any size.
Before we move ahead, let us understand what is Infrastructure as Code and why do we need it.
What is Infrastructure as Code?
Infrastructure as Code (IaC) configures and manages the infrastructure through a descriptive model. It is all about treating your infrastructure configuration and provisioning the same way you treat your application source code. The configuration modules are typically stored in version control systems in well-documented code formats, providing greater accuracy, reducing errors, and increasing speed and consistency. IaC is one of the most critical DevOps practices used with continuous delivery. The benefits that lead many businesses to migrate to IAC are changeless infrastructure, an increase in the speed of delivery, scalability, cost savings, and risk mitigation.
IaC allows DevOps teams to use different tools and approaches to automatically control and customize the required infrastructure instead of manually configuring the servers and operating systems. With the increase in production and delivery cycles, the use of Infrastructure as Code (IaC) tools has changed how software engineers design, test, and release their applications.
Why do we need Infrastructure as Code tools?
Initially, IT managers had to manually install servers, configure them, and deliver programmes to them. The network teams manually stored and handled the configuration data. This was a time-consuming and tedious process. Furthermore, this endeavour necessitated the collaboration of several persons. The most challenging issue was scalability, as administrators struggled to bring up new servers quickly enough to keep up with the speed and scope of changing business operations. Additionally, hiring and managing a team added significantly to the cost.
Organizations could solve some of these problems by deploying multi-cloud and hybrid cloud installations. Disparities that occurred when various personnel performed infrastructure management services, on the other hand, were difficult to control. While they could use scripts to automate some processes, maintaining the infrastructure in the appropriate state was always a struggle. Administrators may now set predefined configurations for each IT resource in source code and automate infrastructure management using infrastructure as code platforms.
How to write Infrastructure as Code?
Infrastructure as Code can be written using anyone of the following approach:
Declarative Approach
Imperative Approach
Declarative (functional): The declarative approach defines the desired state of the target, i.e., What should be the target's actual configuration. The steps to set up a server are not defined. Instead, the list of requirements or third-party software needed to set up the infrastructure or server is defined.
Imperative (Procedural): The imperative approach defines the commands that must be executed to achieve the desired result. The imperative focuses on how the infrastructure can be changed to meet the desired result.
Top Infrastructure as Code Tools
Terraform
HashiCorp Terraform is the most popular and open-source tool for infrastructure automation. It helps in configuring, provisioning, and managing the infrastructure as code. With terraform, you can easily plan and create IaC across multiple infrastructure providers with the same workflow. It uses the declarative approach to define the required infrastructure as code. Terraform allows users to have a pre-execution check to validate whether the configurations meet the result expectations or not before updating or provisioning the infrastructure. It enables users to have their desired infrastructure across multiple cloud providers through a single and consistent CLI workflow. You can quickly provision different environments using the same configuration and manage the entire lifecycle of your desired infrastructure, thus reducing human errors and increasing automation in the infrastructure provisioning and management process.
Ansible
RedHat developed Ansible with an idea to promote simplicity. It contributes towards IT modernization and helps DevOps teams to have faster, more reliable, and coordinated application deployments. You can quickly establish multiple identical environments with security baselines without worrying about fulfilling compliance requirements. As far as business is concerned, Ansible brings in a competitive advantage by providing time for bringing in innovation and strategy within the organization and aligning IT with the business needs.
Ansible is considered the simplest way to automate the provision, configuration, and management of applications and IT infrastructure. Ansible enables users to execute playbooks to create and manage the required infrastructure resources. It does not use agents and can connect to servers and run commands over SSH. Its code is written in YAML as Ansible Playbooks, making it easy to understand and deploy the configurations. You can even expand the features of Ansible by writing your own Ansible modules and plugins.
AWS CloudFormation
AWS CloudFormation is an embedded IaC tool within the AWS cloud platform that provides you with an easy way to quickly and efficiently provision and manage a collection of multiple related AWS and even third-party resources using Infrastructure as Code. It allows you to implement all the required best practices of DevOps and GitOps. With CloudFormation, you can easily manage the scaling of your resources and even automate further resource management by integrating CloudFormation with other required AWS resources. Besides this, AWS CloudFormation also allows you to use its open-source CLI to build your resource providers to provision and manage the third-party application resources along with the native AWS resources.
The models and templates for CloudFormation are written in YAML or JSON format. You just need to code your desired infrastructure from scratch with the suitable template language and use the AWS CloudFormation to provision and manage the stack and resources defined in the template. CloudFormation also uses Rollback Triggers to restore infrastructure stacks to a previously deployed state if errors are observed, to ensure that deployment and upgrading of infrastructure are achieved in a controlled manner.
Azure Resource Manager
Azure Resource Manager is the service provided for deploying and managing Azure resources. An Azure-specific IaC tool allows resources to be deployed, maintained, and tracked in a single collective action rather than individually. It natively incorporates Role-Based Access Control (RBAC) into the resource management mechanism to allow users to apply control of access to all resources within a resource category.
Resource Manager allows you to use declarative templates instead of scripts to manage your infrastructure. With Azure resource manager, you can quickly redeploy your infrastructure solution multiple times throughout the application development lifecycle by effortlessly maintaining consistency in the state.
Google Cloud Deployment Manager
Google Cloud Deployment Manager is an infrastructure deployment service provided by GCP to automate the creation, configuration, provisioning, and management of resources on Google Cloud Platform. You can easily create a set of Google cloud resources and manage them conveniently as a single unit. Using YAML or Python, you can build models, preview what changes will be made before deploying, and view your deployments in a console user interface.
This Infrastructure as Code tool uses a declarative language approach to specify what the configuration is supposed to be and let the system figure out the rest. Google Cloud Deployment Manager provides simultaneous deployments of many resources at once, controls resource creation, and creates resource definition dependencies. Deployment configurations are treated as code, and those deployments can easily be repeated repeatedly by maintaining consistency in their state.
Chef
Chef can be counted among the industry's most notable IaC tools. Chef uses the procedural style language wherein the user has to write the code and step-by-step specify how to achieve the desired state. It depends on the user to determine an optimal deployment process. Using its Ruby-based DSL, Chef allows you to create recipes and cookbooks. These recipes and cookbooks specify the exact steps required to achieve the desired configuration of your applications and utilities on existing servers.
This infrastructure management tool focuses on deploying and modelling a scalable and secure infrastructure automation process across any desired environment. With Chef, DevOps teams can provision and deploy on-demand infrastructure with ease. Chef is one of the most common configuration management solutions enterprises use in their continuous integration and delivery processes.
Puppet
Puppet is yet another open-source configuration management tool that is most commonly used to pull the strings on several application servers at once. It also uses a Ruby-based DSL like chef, where you can describe your infrastructure's desired end state. The primary difference between Puppet and Chef is that it uses a declarative approach, where you have to decide what the configurations you want look like, and then Puppet finds out how to get there.
Puppet refers to a set of IAC tools used to deliver your infrastructures quickly and on a secure scale. It offers a wide group of developers who have built modules that help extend the software's functionality. Puppet integrates with almost all the leading cloud Infrastructure as Code platform providers such as AWS, Azure, Google Cloud, and VMware, enabling multiple cloud automation.
SaltStack
SaltStack is an open-source configuration management tool based on Python that offers a simple solution for provisioning, deploying, and configuring infrastructure on any platform at a high-speed rate.
SaltStack focuses on the automation of infrastructure, security, and network within the organization. It is an easy-to-use IaC tool that proves to be very useful during the mitigation and remediation of common infrastructure issues. It is a secure and cost-efficient IaC solution that provides automation and orchestration and reduces manual effort. If required, it can automatically detect problems with event triggers and return to the desired state. Salt even has SSH support that can support agentless mode. It has a scheduler that lets you specify how often the managed servers should run your code.
( R )?ex
(R)?ex or Rex is an easy to use automation framework that doesn't enforce any model of its own on the user. With rex, it's your choice to use any combination of declarative or imperative approach, push or pull management style, local or remote execution, etc. It is an open-source deployment and configuration management platform that is just all about Perl Coding using which you can seamlessly extend the modules as per your requirement. Its SSH support to control remote hosts makes it easy to onboard and effectively automate repeatable tasks, thus saving human effort and time.
Vagrant
Vagrant is yet another of the best IaC tools developed by the Terraform creators, HashiCorp. The difference is that Vagrant focuses on building computing environments that use a limited number of virtual machines rather than massive cloud infrastructure environments that can span hundreds or thousands of servers over several cloud providers.
HashiCorp Vagrant is a simple yet powerful tool focused on making development environments easier. It promotes the use of unified workflows by leveraging declarative configuration files containing all the required configuration details. It enforces state consistency across environments and supports integration with existing configuration management tools like Puppet, Chef, SaltStack, Ansible, etc.
Pulumi
Pulumi is an IaC tool that sets itself apart from the rest Infrastructure as Code platforms by providing greater flexibility. It supports several programming languages such as Python, JavaScript, C#, Go, and TypeScript. By providing more support for language options, Pulumi can fit a greater variety of IaC DevOps use cases and reach the majority of developers. More languages also mean that you have more tools and frameworks readily available for building and testing your infrastructure.
A unique aspect of Pulumi as Infrastructure as Code tool is that it does an excellent job keeping core concepts and features of established tools such as Terraform, while offering support for the cloud giants AWS, GCP, and Azure Cloud. Additionally, it has automation options for;
Deployment delivery
Quality assurance using policies
Easy auditioning
Comprehensive identity control
How do you choose the best IaC Tool for organization?
There are different tools in IaC because not the same tool can perform all the tasks. The tools are defined in three main categories :
Infrastructure provisioning
Configuration of Provisioned infrastructure
Application deployment
And the phases in which they automate tasks :
Initial Setup phase
Maintaining phase
There is one more category in which we can divide the tools is "how they work"
Declarative or imperative
Mutable or Immutable
Agent or Agentless
We have several tools available to automate the infrastructure, and we have divided the tools into different categories. Now let us understand when we should choose which IaC tool.
For configuration Management vs. Provisioning
Ansible, Chef, Puppet, and salt stack are configuration management tools to install and configure the applications on existing infrastructures. Whereas terraform and cloud formation are infrastructure provisioning tools, they can be used to provision the servers and other infrastructure like load balancers, databases, networking configuration. Some tools can perform both tasks. For example, Terraform can do both infrastructure provisioning as well application deployment.
For Mutable Infrastructure vs. Immutable Infrastructure
Chef, Puppet, Ansible, and SaltStack are all mutable infrastructure tools by nature. If you configure these tools to install a new version of an existing package or software, it will install the software update on your existing servers and make the changes in real-time.
Whereas for a tool like Terraform (an immutable IAC tool), every "change" is a new server deployment.
For Procedural vs. Declarative
Chef and Ansible follow the procedural approach as we have to write code that specifies the step-by-step to achieve the target state. Terraform, CloudFormation, SaltStack, and Puppet all use a declarative method, in which we write code that defines the target state we want to achieve, and the IAC tool figures out how to get there.
For Agent vs. Agentless
Chef, Puppet, and SaltStack are agent-based tools that involve the installation of an agent on the target computer. This agent usually runs in the background on the target machine and carries out the operations necessary to achieve the goal. On the other hand, No agents are needed for Ansible, CloudFormation, or Terraform. Some of them need agents, but these are usually included in the infrastructure we use.
For Provisioning and Configuration Management
Ansible and Terraform are the tools that can perform both provisioning and Configuration management. Ansible and Terraform can work together. We can use Terraform to provision infrastructure, databases, load balancer, network topology, etc. Ansible can be used to deploy applications on top of these infrastructures.
Conclusion
We believe that IAC is the future of computing resource provisioning and management. While it comes with its own set of implementation challenges, the benefits it delivers, in the long run, surpass the hurdles it faces at present. The IT and DevOps teams benefit from Infrastructure as Code (IAC) greatly.
IaC tools prove to be the critical components in making this implementation possible. The above list provides you with some of the top IaC tools in the market today. This list is certainly not exhaustive but will help you to get a starting point in this field.