What is Ansible?
Depending on your role in the workplace, you may have already heard about Ansible if you work in the IT sector. The CIO described it as being the darling of DevOps for anything and everything related to software automation. Within a short period of time, it has appeared out of nowhere to become the best choice for the majority of IT automation tasks. StackShare listed thousands of organizations that use Ansible to automate their processes, including NASA, Apple, Intel, Hootsuite, Evernote, and more.
So, what does Ansible do and why has it become so popular almost overnight? Here in this article, we are going to delve into multiple aspects of Ansible so that you can understand what makes it so powerful and grasp its importance in the current software automation industry. But before we jump into the details, let’s start by giving you two real-life examples if you are new to Ansible.
Two Real-world Examples where Ansible can save the day
Suppose you want to install a web browser tool like Google Chrome on a network that consists of hundreds or thousands of computer systems, so what would you do? Obviously, you are not going to access each of the systems to install chrome in them.
Think of your application experiencing a sudden surge in traffic and getting crashed frequently as a result. A thorough analysis revealed that the poor infrastructure configuration was to blame. You would like to upgrade the current infrastructure because it cannot cope with the growing workload. Now what you need to do is deploy additional infrastructure or servers that also need to be deployed quickly while installing the same configuration on them at the same time. The main issue is that a manual process will not only be slower, but it will also be prone to human error.
This is where Ansible comes into play, enabling you to accomplish your goal in an effective and streamlined manner. Ansible is an IaC tool, or Infrastructure as Code tool, and in these two real-world scenarios, it enables you to add the infrastructure and set it up quite effortlessly.
Now that you have a basic understanding of how Ansible plays a fundamental role in managing configuration, updating servers and workstations, orchestrating intra-services, deploying cloud frameworks, managing applications across infrastructure, and other vital IT automation needs, let us dive deeper into the topic.
What is Ansible in a Nutshell?
In a nutshell, it’s a simple yet very powerful open-source automation engine for a wide range of diverse and cross-platform IT tasks. It is designed to get rid of most of the manual grind from a typical IT environment and enhance its consistency, scalability, and reliability up to a few steps ahead. Since Ansible doesn’t come with extra security infrastructure and has no dependency on agent software, deployment becomes easy.
Now, as automation is what Ansible does, you need to provide instructions for each task to complete. Also, those instructions can be written in simple and user-friendly script form, so version control is no longer a thing to worry about.
It has resulted in huge contributions to the concept of IaC or Infrastructure as Code in the software and IT industry. IaC makes it possible to maintain client infrastructure and server infrastructure just as software development has long been done. IaC now makes all this possible because the system can run uninterrupted without requiring frequent staff input.
Although Ansible is mainly used in large IT automation frameworks, that doesn’t mean it’s not useful for regular everyday use cases. The fact that you, being a system administrator, can not only configure a single computer but a big network of systems using Ansible quite easily – makes it a highly sought-after tool for anybody whose job involves such responsibilities.
Moreover, Ansible instructions are written in the form of YAML templates, which are human-readable and don’t require one to learn any special programming language.Thus anyone can learn and execute the program regardless of their ability to program or whether they are a beginner or expert developer
How does Ansible work?
Ansible divides your system into two categories – the computer in which you run Ansible is called the control node, and the rest of the systems are called managed nodes. To run Ansible, your system must include a minimum of one control node computer, and although not necessary, sometimes another control node as a backup should be added depending on what you are trying to accomplish.
Managed note, on the other hand, is any device or computer that you intend to manage by the control node.
Coming to how Ansible works, it connects the nodes, which can be servers, clients, or anything you want to configure, and sends out an Ansible module to your node. Ansible modules are basically small programs with instructions to carry out certain automation tasks. These modules are executed over SSH and then removed by Ansible when the task intended is finished.
- Since Ansible works in agentless mode, it doesn’t require the managed nodes to have software installed on them already.
- Ansible control nodes are required to have login access to the computers it is managing, i.e. the managed nodes to execute the modules.
- While you can provide access through SSH keys, which is the primary way, it supports other authentication methods as well. There is no need of providing the Root login, any user login would work.
- Once the connection has been established, Ansible starts transferring the modules to the remote nodes for execution according to your instruction or playbook.
- Ansible gets instructions about which nodes to manage from the inventory. It comes with a built-in inventory, but users can create and use their own to specify which machines they want managed by Ansible.
- A user can either use Ansible’s default modules to automate jobs or can script their own. You can use a variety of languages like Python or Ruby that are able to return JSON to create Ansible modules. What’s more, if you are writing modules for Windows automation, you can even use Powershell.
- Ansible also works without modules – in that case, scripting and ad-hoc commands are used. In order to run ad-hoc commands, a user needs to call modules or run commands directly from the command line. There is no need to use a Playbook in this case. However, while you can do this for a simple one-time job, the use of Ansible playbooks is a must for anything more complicated.
What things you can Automate by using Ansible?
Nothing to worry about if you find the Ansible module challenges. Most of its complications are handled by the tool itself, and the user doesn’t have much to do. Ansible modules act as models of what the user desires in a system where each module decides its role according to the same without further user intervention.
For example, consider a network consisting of multiple workstations where the administrator wants every system within the network to have a certain version of software installed. Now it’s the Ansible module that will decide whether each managed node has that version already and should it be able to detect a node with a different version, then it executes the necessary task to upgrade to the version it has been instructed. That means a company can keep all its computers updated at all times without any human intervention.
Infrastructure maintenance involves more than checking software versions and updating them; it also involves monitoring your network. It’s the modules of Ansible that are responsible for performing the specific jobs when we refer to Ansible. If you want to automate something across multiple computers, explore the Ansible modules that can handle the same task. If you are an expert Ansible coder, you can create modules customized for your intended tasks.
Prominent Features of Ansible
1. Configuration Management
Ansible is designed to make configuration management straightforward, consistent, and safe without any chance of unintended error. For an IT expert in the related area, it’s easy to start using Ansible for a certain automation job minus a learning curve and hassle. Configurations that are used in Ansible are simple infrastructure descriptions that both machines can parse and humans can read easily.
2. Application Deployment
With Ansible, one can deploy multi tier applications easily and quickly. There is no need of writing custom codes for automation; all you need to do is write a Playbook by listing the jobs you want to do and let Ansible figure out how to accomplish the tasks and take your system to be at the state you desire. In short, configuring applications manually on every system is no longer necessary.
Orchestration, in its classic sense, means arranging various elements in unison to make them perform smoothly and beautifully. Like a musical conductor directs a host of different instruments to create an amazing artistic singular orchestra, Ansible lets you do the same with different elements within an infrastructure. When you need to deploy applications, managing merely the front and backend services isn’t enough, but multiple different things such as storage, networks, databases, and others are also involved in the process. Ensuring all the tasks are being executed in the proper intended way is also crucial. Here Ansible does its magic. It automates workflows, provisions, and more to orchestrate the tasks effortlessly. Moreover, since Ansible Playbooks are portable, one can use the same orchestration in other cases as well once the infrastructure is defined.
4. Cloud Provisioning
Ansible can automate the provision of cloud infrastructure, network devices, virtual hosts, and physical servers easily.
5. Security and Compliance
Similar to the app deployment, security and compliance policies like locking specific users down or defining firewall rules can also be implemented sitewide using Ansible. You need to make a security configuration on the control node and then the associated Ansible Playbook will make sure the managed nodes are updated in accordance to the same automatically. Furthermore, Ansible comes with an additional security feature where it ensures the admin login details can’t be retrieved in a readable text form.
Architecture of Ansible
Let’s see what parts make the whole Ansible structure up.
These are small programs that Ansible sends out from the control node to all the managed nodes. Ansible Playbooks are responsible for the execution of modules to control packages, files, and services. Once the intended task is completed, these modules are removed from the managed systems. You can find around 450 modules designed to handle most regular IT automation tasks.
You can compare Ansible Playbook with any instruction guide and it is written using YAML language. YAML is a simple machine-parsable and human-readable coding language; therefore anybody with little or no prior knowledge of Ansible would be able to grasp the concept easily, which is one of the primary reasons behind Ansible’s popularity.
Every Playbook consists of one or more than one Play, and these Plays, while running sequentially, define the roles of hosts as per given tasks.
Plugins, like in any other platform or tool, are extra codes designed for additional functionalities. While there are lots of plugins that come with Ansible, a user can also write a custom one for their specific needs. Cache, callback, and actions are some of the common plugins found in Ansible.
There are multiple APIs available so that one can further extend callbacks, connection protocols, and more. For instance, instead of having to use only the SSH key, you can easily choose from other connection options using specific APIs.
Inventory is another simple file that lists all systems, including the control node and managed nodes, with their specific details like IP addresses, servers, databases, and more. After the inventory is registered, one can add variables to a host using simple texts easily.
Undoubtedly, Ansible comes with several key advantages that collectively made it so popular so quickly. Find below the main benefits Ansible has to offer for the global IT automation industry today.
1. Little or no learning curve
When it comes to Ansible advantages, its simplicity must come at the top of the list. And when we are talking about Ansible simplicity, we don’t only mean IT professionals, but for the newbies who want to try their hands on it as well. Since Ansible enjoys simple and easily comprehensible documentation, the learning curve is almost flat here. So a user can understand the workflow and the logic behind it to improve their productivity in literally no time.
Moreover, due to the no dependency system, Ansible performs its tasks sequentially. The process stops the moment it identifies an error, making the troubleshooting pretty straightforward for even a novice user.
2. The use of already widespread Python as the core language
Python is the core language in which Ansible is written, and that is another of its major benefits. While it’s human-readable as well as machine-parsable at the same time, one can easily find Python libraries on most of the Linux distros in-built.
3. Ansible is agentless
Ansible has zero dependencies on agents. In Ansible, communication between master and agent is carried out through Paramiko or SSH, meaning it doesn’t require the presence of any pre-installed agents on managed nodes to ensure the intended operation. This agentless feature helps to reduce maintenance jobs significantly.
4. Ansible Playbooks use YAML language
Playbooks are files that include configuration instructions for Ansible and YAML is used to compose them. YAML’s advantage of being the better language for automation and its management over others makes Ansible a superior tool.
5. Ansible Galaxy
It’s a portal that works as a central library for storing and sharing content related to Ansible. As a result of Galaxy, people can easily download reusable standard Roles for server configuration or application deployment without having to write custom modules or Playbooks on their own, which adds a lot to the simplicity and speed of an operation.
Now as you already went through its advantages, let us have a look at some of the difficulties you may experience when using Ansible.
1. Lack of a Convenient UI
Ansible’s crude UI is one of its primary setbacks and can discourage users from using it to some extent. For the major part of its existence, Ansible only had a basic command-line interface. Later a graphic AWX UI was added to make the tool somewhat user-friendly, which turned into a web management user interface subsequently to be called Ansible Tower. Though it’s still going through the development phase and a wide room for improvement in the UI section remains even in the present day.
2. No Notion of State
Ansible, unlike other standard automation solutions like Puppet, does not come with a Notion of State, meaning there’s no dependency tracking. For those who want their automation tool to keep an elaborate catalog so that they can reach a certain state without influencing the environment, Ansible offers no option.
3. Lack of sufficient Windows Support
Coming to the next disadvantage, which is the limited support for Windows operating systems in Ansible. Although its version 1.7 does support Windows along with Linux nodes, Ansible makes use of Powershell instead of the SSH key. This means the user must employ a Linux-powered control node to execute tasks in the Windows-based managed nodes.
4. Ansible has Limited Enterprise Experience
Automation tools such as Chef and Puppet enjoy full-fledged practical work experience with big enterprises; something that Ansible, being a newer entry in the market, lacks. Therefore Ansible’s accountability as an automation tool is not as regarded as its competitors.
5. It’s relatively new in the IT Automation Field
Since Ansible started gaining popularity just recently, a considerable number of organizations and IT experts are still skeptical about its reliability. While the competing tools come with a large user and developer community, Ansible is still far from reaching that state. Its newcomer status further implies the potential presence of undiscovered issues and bugs.
Ansible Best Practices for Beginners
If you are new to Ansible, below are a few best practices you want to follow religiously to make sure you manage the infrastructure efficiently. Even though Ansible is quite forgiving for anyone who just started, thanks to its simple and understandable language, features, and functionalities, one should not overlook the standard working methods suggested by veteran Ansible users as described here.
1. Name the Tasks
Although it’s an optional feature, you should name your tasks according to output.
2. Make use of Commenting Feature
This makes your codes easily comprehensible to the others who will read them.
3. Using Version Control is Essential
Mention the inventory, roles, and variables here to ensure an audit trail to identify the user and timestamp of each code-changing event.
4. Choose from a wide range of already Coded Modules
You can largely benefit from a huge library of 750+ ready-made modules for most standard tasks. These modules have been tested and utilized by numerous users every day, so you can rest assured of their reliability without the fear of encountering any bugs.
5. Test your Changes, then Rinse and Repeat
Whatever changes you do, test the same extensively to get valuable insights into how effectively you have been able to implement the configuration.
Ansible has lately become one of the most used DevOps tools, and for all the right reasons. It performs crucial tasks that if otherwise done manually, could be repetitive, enormously complicated, error-prone, and take a lot of time. Using Ansible can greatly simplify tedious processes by allowing you to automate them effectively.
Here in this brief piece, we made sure to focus on all the vital aspects of Ansible and explained them in an easy-to-understand manner. To sum it up, no matter if you are looking to make your IT job a little less complex by automating and streamlining some regular operations or interested in becoming a DevOps expert, Ansible offers unbeatable traits that no other automation tool can.
To learn how to use Ansible’s full potential, we recommend you start from here on this page and browse the rest of the sections of our site for more in-depth knowledge. We will update this page with related training materials and videos and other sources, so make sure you visit us frequently.