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Most Used Ansible Modules

Ansible is a radically simple IT automation engine that automates cloud provisioning, configuration management, application deployment, intra-service orchestration, and many other IT needs.

It uses no agents and no additional custom security infrastructure, so it’s easy to deploy – and most importantly, it uses a very simple language (YAML, in the form of Ansible Playbooks) that allow you to describe your automation jobs in a way that approaches plain English.

Ansible has three main files that you need to consider:

  • Host/inventory file: Contains the entry of the nodes that need to be managed
  • Ansible.cfg file: Located by default at /etc/ansible/ansible.cfg
  • Main file: A playbook that has modules that perform various tasks on a host listed in an inventory or host file

Module : Package management (YUM, DNF, APT)

Here are you can found all modules on Ansible document website. Various packaging modules available in Ansible as it support various OS, Language, you can found it here

This installs the Apache web server and the MariaDB SQL database. 

- name: install the latest version of Apache and MariaDB
  dnf:
    name:
     - httpd
     - mariadb-server
    state: latest

This installs the list of packages and helps download multiple packages.

- name: Install a list of packages
  yum:
    name:
     - nginx
     - postgresql
     - postgresql-server
    state: present

Module : Service

Controls services on remote hosts. Supported init systems include BSD init, OpenRC, SysV, Solaris SMF, systemd, upstart.

This start Apache service

- name: Start service httpd, if not started
  service:
    name: httpd
    state: started

This restarts the network service of the interface eth0.

- name: Restart network service for interface eth0
  service:
    name: network
    state: restarted
    args: eth0

Module : Template

- name: Template a file to /etc/files.conf
  template:
    src: /mytemplates/foo.j2
    dest: /etc/file.conf
    owner: bin
    group: wheel
    mode: '0644'

Module : Copy

The copy module copies a file from the local or remote machine to a location on the remote machine.

- name: Copy file with owner and permission, using symbolic representation
  copy:
    src: /src/path/tofile
    dest: /dest/patch/tofile
    owner: foo
    group: foo
    mode: u=rw,g=r,o=r

Module : Debug

The debug module prints statements during execution and can be useful for debugging variables or expressions without having to halt the playbook.

- name: Display all variables/facts known for a host
  debug:
    var: hostvars[inventory_hostname]
    verbosity: 4

This displays all the variable information for a host that is defined in the inventory file.

This registers the content of the copy module output and displays it only when you specify verbosity as 2. For example:

ansible-playbook demo.yaml -vv

Module : File

The file module manages the file and its properties.

  • It sets attributes of files, symlinks, or directories.
  • It also removes files, symlinks, or directories.

The below creates a file named foo.conf and sets the permission to 0644.

- name: Change file ownership, group and permissions
  file:
    path: /etc/foo.conf
    owner: foo
    group: foo
    mode: '0644'

Module : Lineinfile

The lineinfile module manages lines in a text file.

  • It ensures a particular line is in a file or replaces an existing line using a back-referenced regular expression.
  • It’s primarily useful when you want to change just a single line in a file.

This sets the value of SELINUX=enforcing.

- name: Ensure SELinux is set to enforcing mode
  lineinfile:
    path: /etc/selinux/config
    regexp: '^SELINUX='
    line: SELINUX=enforcing

This adds an entry for the IP and hostname in the resolv.conf file.

- name: Add a line to a file if the file does not exist, without passing regexp
  lineinfile:
    path: /etc/resolv.conf
    line: 192.168.1.99 foo.lab.net foo
    create: yes

Module : Git

The git module manages git checkouts of repositories to deploy files or software.

# Example Create git archive from repo
- git:
    repo: https://github.com/ansible/ansible-examples.git
    dest: /src/ansible-examples
    archive: /tmp/ansible-examples.zip

This clones a repo with a separate Git directory.

- git:
    repo: https://github.com/ansible/ansible-examples.git
    dest: /src/ansible-examples
    separate_git_dir: /src/ansible-examples.git

Module : Cli_command

The cli_command module, first available in Ansible 2.7, provides a platform-agnostic way of pushing text-based configurations to network devices over the network_cli connection plugin.

This sets the hostname for a switch and exits with a commit message.

- name: commit with comment
  cli_config:
    config: set system host-name foo
    commit_comment: this is a test

This backs up a config to a different destination file.

- name: configurable backup path
  cli_config:
    config: "{{ lookup('template', 'basic/config.j2') }}"
    backup: yes
    backup_options:
      filename: backup.cfg
      dir_path: /home/user

Module : Archive

The archive module creates a compressed archive of one or more files. By default, it assumes the compression source exists on the target.

- name: Compress directory /path/to/foo/ into /path/to/foo.tgz
  archive:
    path: /path/to/foo
    dest: /path/to/foo.tgz
- name: Create a bz2 archive of multiple files, rooted at /path
  archive:
    path:
   - /path/to/foo
    - /path/wong/foo
    dest: /path/file.tar.bz2
    format: bz2

Module : Command

One of the most basic but useful modules, the command module takes the command name followed by a list of space-delimited arguments.

- name: return motd to registered var
  command: cat /etc/motd
  register: mymotd
- name: Change the working directory to somedir/ and run the command as db_owner if /path/to/database does not exist.
  command: /usr/bin/make_database.sh db_user db_name
  become: yes
  become_user: db_owner
  args:
    chdir: somedir/
    creates: /path/to/database
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