Automating software installation and configuration tasks is fundamental for efficient DevOps practices. Ansible, an open-source automation tool, works on this interaction by permitting you to characterize the framework as code and automate tasks across various servers. In this article, we will zero in on utilizing Ansible to introduce Apache Tomcat, a broadly utilized Java Servlet compartment, on servers inside your infrastructure.

Apache Tomcat is a vital part of sending Java-based web applications, giving a solid and versatile environment for hosting servlets and JSP pages. However, manually installing and arranging Tomcat on various servers can be time-consuming and error-prone. Ansible streamlines this interaction by empowering you to define declarative configuration files called playbooks, which indicate the ideal condition of your foundation and the tasks to be executed.

Ansible is an open-source automation tool designed for configuration management, application organization, and assignment coordination. It allows system administrators and DevOps groups to automate repetitive tasks, smooth out complex work processes, and oversee infrastructure productively.

What Is Ansible?

Ansible works by pushing changes out to all your servers and re-quires no extra software to be installed on your servers (thus no extra memory footprint and no extra daemon to manage), unlike other configuration management tools like Puppet and Chef.

Configuration management is all about taking your hosts and getting them to their end desired state. So we don’t necessarily know what the state is now, but we can declare the desired end state, and config management tools are really good about taking you from where you are to where you want to go

At its center, Ansible works utilizing a basic and agentless architecture, making it simple to convey and use across different conditions. It uses SSH connections to speak with remote servers and execute tasks defined in YAML-formatted configuration called playbooks. Playbooks portray the ideal condition of systems and characterize the undertakings to accomplish that state.

Key Highlights Of Ansible

• Idempotent Execution: Ansible ensures that undertakings are idempotent, meaning they can be executed on various occasions without changing the system state assuming the ideal state has proactively been accomplished.
• Declarative Configuration: Playbooks portray the ideal end-condition of systems as opposed to the step-by-step strategies to accomplish it, giving a clear and brief method for managing infrastructure.
• Infrastructure as Code (IaC): Ansible advances the idea of the framework as code, permitting infrastructure to be characterized, versioned, and overseen close by application code.
• Extensibility: Ansible gives a great many modules and modules to interface with different systems and services, empowering integration with existing tools and innovations.
• Community and Ecosystem: Ansible advantages from a large and dynamic local area, with an abundance of resources, modules, and most ideal practices that anyone could hope to find for clients.

Ansible Architecture

Ansible architecture is designed to provide a simple, scalable, and agentless automation solution for managing infrastructure and applications. At its core, Ansible follows a client-server model, where a central control node communicates with managed nodes (servers or devices) over SSH or PowerShell remoting. Let’s break down the components of the Ansible architecture:

Control Node:

• The control node is where Ansible is installed and from where automation tasks are orchestrated.
• It contains the inventory, playbooks, roles, and configuration files important to define and execute automation tasks.
• Ansible commands and playbooks are executed from the control node.

Managed Nodes:

• Managed nodes are the servers, devices, or infrastructure parts that Ansible manages and automates.
• Ansible interfaces with managed nodes over SSH (for Unix/Linux systems) or PowerShell remoting (for Windows systems).
• Managed nodes does not require no particular software or agents to be installed, making Ansible lightweight and agentless.

Inventory:

• Ansible uses an inventory, which is a file with list of remote servers to communicate with much like hosts file (/etc/hosts). Inventory holds list of hosts, and also allows you to group hosts together by a group name and you can use those groups as part of your targets

Modules:

• Ansible ships with a number of modules that can be executed directly on remote hosts or through Playbooks
• These modules can control system resources, like services, packages, files (anything really), or handle executing system commands.
• Modules (also referred to as “task plugins” or “library plugins”) are discrete units of code that can be used from the command line or in a playbook

Playbooks:

• Playbooks are YAML-formatted documents that define a set of automation tasks, known as plays.
• Like many other configuration management tools, Ansible uses a metaphor to describe its configuration files as ‘playbooks’
• In Ansible, you write playbooks (a list of instructions, describing the steps to bring your server to a certain desired configuration state), that are then played on a particular server or set of servers.
• A playbook contains one or more plays, which in turn may contain one or more tasks

Roles:

• Roles are collections of playbooks, variables, and templates coordinated into a directory structure.
• They give a method for package and reuse automation logic across various projects or environments.
• Roles encapsulate normal tasks or configurations, making them secluded and simple to keep up with.

Step-By-Step Process to Install tomcat using ansible playbook

Step-1: Launch an EC2 Instance

Launch EC2 instance with Amazon Linux2 Kernel 5.10(AMI) along with port numbers set SSH – 22, HTTP 8o and select storage t2.micro.

Now connect with git bash or any other terminals as you like.

Step-2:

Now install Ansible to our local machine by using following command

sudo amazon-extras-linux install ansible2

Step-3: Create a inventory file

In this section we creating inventory file and inside that file we are providing hosting address. Create file by using following command

vi <filename.ini>

# inventory.ini

[web_servers]
server1.example.com ansible_user=ec2-user ansible_ssh_private_key=~/.ssh/my_private_key.pem 
server2.example.com ansible_user=ubuntu ansible_ssh_private_key=~/.ssh/my_key.pem
[db_servers]
db1.example.com ansible_user=admin ansible_password=my_password
db2.example.com ansible_user=admin ansible_password=my_password

Step-4: Creating playbook

In this section we are creating playbook by using following command

vi playbook.yml

Playbooks are written in YAML Configuration. For YAML configuration we need “.yml” extension

- name: Install Tomcat
  hosts: tomcat_servers
  become: true
  tasks:
    - name: Install Java
      yum:
        name: java-1.8.0-openjdk
        state: present
    - name: Download Tomcat
      get_url:
        url: "https://archive.apache.org/dist/tomcat/tomcat-9/v9.0.54/bin/apache-tomcat-9.0.54.tar.gz"
        dest: /opt/
    - name: Extract Tomcat
      unarchive:
        src: /opt/apache-tomcat-9.0.54.tar.gz
        dest: /opt/
        remote_src: yes
    - name: Configure Tomcat Users
      template:
        src: tomcat-users.xml.j2
        dest: /opt/apache-tomcat-9.0.54/conf/tomcat-users.xml
    - name: Start Tomcat Service
      service:
        name: tomcat
        state: started
        enabled: yes

Step-5: Run the Playbook

Execute the playbook using the ansible-playbook command, specifying the inventory file.

ansible-playbook -i <filename.ini> <filename>.yml

Step 6: Verify Installation

Now access Tomcats’ management console through a web browser (http://<server_ip>:8080) to verify that Tomcat is installed and running correctly.

Conclusion

In conclusion, deploying Apache Tomcat using an Ansible playbook offers a streamlined and repeatable way to deal with managing Tomcat installations across different servers. By characterizing installation steps, configuration management, and service management tasks inside the playbook, administrators can ensure consistency and dependability in the deployment cycle. Ansible’s idempotent nature ensures that playbook executions are idempotent, meaning they can be securely re-run without causing accidental changes or interruptions. Also, the utilization of Ansible playbooks advances infrastructure as code works on, empowering version control, collaboration, and automation in Tomcat deployment work processes. Generally speaking, utilizing Ansible for Tomcat installation works on organization tasks, speeds up sending cycles, and improves the viability of Tomcat installations in big enterprise conditions.

Tomcat Using Ansible Playbook – FAQ’s

Could Ansible install Tomcat on multiple servers at the same time?

Yes, Ansible can install Tomcat on different servers all the while by defining the objective hosts in the inventory file and specifying them in the playbook. Ansible’s equal execution capacity ensures productive and simultaneous deployment across various servers.

Does Ansible handle dependencies for Tomcat installation consequently?

Ansible can manage dependencies for Tomcat installation in view of the package manager of the target working system. Users can determine package dependencies in the playbook, and Ansible will ensure they are installed before Tomcat installation.

Could I configure custom settings for Tomcat (e.g., server.xml) utilizing Ansible?

Yes, Ansible allows users to manage configuration files for Tomcat, for example, server.xml, by defining tasks in the playbook. Users can layout arrangement files and deploy them to target servers, ensuring consistency and adherence to desired settings.

How would I deal with authentication for deploying Tomcat with Ansible?

Ansible supports different authentication techniques, including SSH keys and secret key confirmation. Users can arrange confirmation settings in the Ansible inventory file or utilize dynamic inventory scripts to safely manage credentials.

Is it possible to upgrade Tomcat versions using Ansible playbooks?

Yes, Ansible allows users to automate the method involved with updating Tomcat versions by defining tasks to uninstall the current version and introduce the new version. By utilizing idempotent undertakings, Ansible ensures that upgrades are executed dependably and reliably across multiple servers.