https://docs.ansible.com/ansible/latest/command_guide/command_line_tools.html

ansible-rulebook : start a playbook based on a specific event

https://blog.stephane-robert.info/post/ansible-event-driven/

ansible-pull : opposite to ansible is based on the push mode, offering a central management, the pull mode can be use in specific cases

https://blog.octo.com/ansible-pull-killer-feature

ansible-galaxy : get collections of playbooks

ansible : Define and run a single task ‘playbook’ against a set of hosts

ansible-playbook : Define and run a single task ‘playbook’ against a set of hosts

ansible-config : View ansible configuration

ansible-console : REPL console for executing Ansible tasks

ansible-doc : plugin documentation tool

ansible-galaxy : Perform various Role and Collection related operations

ansible-inventory : Show Ansible inventory information, by default it uses the inventory script JSON format

ansible-vault : encryption/decryption utility for Ansible data files

ansible-lint : check playbook syntax

# ansible all -m ping 
# ansible -vvv -i "node1," all -u user1 -m ping       # debug
# ansible foo.example.com -m yum -a "name=httpd state=installed"
# ansible -i hosts all -m yum -a 'name=ncdu state=present'
# ansible -i hosts all -m yum -a 'name=ncdu state=absent'
# ansible foo.example.com -a "/usr/sbin/reboot"
# ansible aix1 -m script -a "./myscript.sh"

Commands modules for ansible

command
expect
psexec (for windows)
raw
script
shell
telnet

Only way to pass a command on target without python installed

# ansible myhost --become -m raw -a "yum -y install python"

ansible-inventory --list
ansible-inventory -i ./sample.yml --graph
ansible-config dump --only-changed
ansible -m module_name -a attributes

ansible-config dump
ansible-config list
ansible-config view

# ansible all -m ping --one-line
lnx80 | SUCCESS => {"changed": false,"ping": "pong"}
lnx81 | SUCCESS => {"changed": false,"ping": "pong"}
aix01 | SUCCESS => {"changed": false,"ping": "pong"}
aix20 | SUCCESS => {"changed": false,"ping": "pong"}

$ ANSIBLE_REMOTE_USER=user01 ansible all -k -K -m ping
SSH password:
BECOME password[defaults to SSH password]:
         172.16.120.155 | FAILED! => {
    "msg": "Using a SSH password instead of a key is not
    possible because Host Key checking is enabled and sshpass
    does not support this.  Please add this host's fingerprint
    to your known_hosts file to manage this host."
    }
         172.16.120.122 | FAILED! => {
    "msg": "Using a SSH password instead of a key is not
    possible because Host Key checking is enabled and sshpass
    does not support this.  Please add this host's fingerprint
    to your known_hosts file to manage this host."
}
         172.16.120.123 | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/libexec/
        platform-python"
    },
    "changed": false,
    "ping": "pong"
}

File conversion:

[root@srv1]/usr/bdl/ansible# ansible-inventory -i inventory/hosts --list
{
    "ALL": {
        "children": [
            "cluster",
            "test1"
        ]
    },
    "_meta": {
        "hostvars": {}
    },
    "all": {
        "children": [
            "ALL",
            "empty",
            "managedClients",
            "ungrouped"
        ]
    },
    "cluster": {
        "hosts": [
            "cl1labo",
            "cltest"
        ]
    },
    "test1": {
        "hosts": [
            "laboh"
        ]
    }
}

[root@srv1]/usr/bdl/ansible# ansible-inventory -i inventory/hosts --list --yaml
all:
  children:
    ALL:
      children:
        cluster:
          hosts:
            cl1labo: {}
            cltest: {}
        test1:
          hosts:
            laboh: {}
    empty: {}
    managedClients: {}
    ungrouped: {}

# cat copy_file.yml
---
 - hosts: app
   tasks:
     - name: Fetch the file from the mwiapp01 to master
       run_once: yes
       fetch: src=/tmp/app01-to-app02.jar dest=buffer/ flat=yes
       when: "{{ inventory_hostname == 'mwiapp01' }}"

     - name: Copy the file from master to mwiapp02
       copy: src=buffer/app01-to-app02.jar dest=/tmp/
       when: "{{ inventory_hostname == 'mwiapp02' }}"

# cat fiwalld.yml
---
 - name: FirewallD
   hosts: localhost
   connection: local
   tasks:
    - name: FirewallD rules
      firewalld:
        permanent: yes
        immediate: yes
        service: "{{ item }}"
        state: enabled
      with_items:
       - http
       - https
   tasks:
    - name: FirewallD rules
      firewalld:
        permanent: yes
        immediate: yes
        port: "{{item.port}}/{{item.proto}}"
        state: "{{item.state}}"
        zone: "{{item.zone}}"
      with_items:
       - {port: "8080", proto: "tcp", state: "disabled", zone: "public" }
       - {port: "161-162", proto: "udp", state: "disabled", zone: "internal" }
       - {port: "9001", proto: "tcp", state: "enabled", zone: "public" }
   tasks:
    - name: FirewallD rules
      firewalld:
        permanent: yes
        immediate: yes
        rich_rule: "{{ item }}"
        state: enabled
      with_items:
       - 'rule service name="ftp" audit limit value="1/m" accept'
       - 'rule service name="http" audit limit value="1/m" drop'
   tasks:
    - name: FirewallD rules
      firewalld:
        permanent: yes
        immediate: yes
        rich_rule: "{{ item }}"
        state: enabled
      with_items:
       - 'rule forward-port port=8080 protocol=tcp to-port=80 family=ipv4'

---
- hosts: all
  become: true

  handlers:
    - name: restart ssh
      service: name=sshd state=restarted

  tasks:
    # Use secure and encrypted communication.
    - name: Allow sshd to listen on tcp port 2849.
      seport:
        ports: 2849
        proto: tcp
        setype: ssh_port_t
        state: present
      when: ansible_selinux.status == 'enabled'

    - name: Update SSH configuration to be more secure.
      lineinfile:
        dest: /etc/ssh/sshd_config
        regexp: "{{ item.regexp }}"
        line: "{{ item.line }}"
        state: present
        validate: 'sshd -t -f %s'
      with_items:
        - regexp: "^PasswordAuthentication"
          line: "PasswordAuthentication no"
        - regexp: "^PermitRootLogin"
          line: "PermitRootLogin no"
        - regexp: "^Port"
          line: "Port 2849"
      notify: restart ssh

    # User account configuration.
    - name: Add a deployment user.
      user:
        name: johndoe
        state: present

    # Disable root login and use `sudo`.
    - name: Add sudo rights for deployment user.
      lineinfile:
        dest: /etc/sudoers
        regexp: '^johndoe'
        line: 'johndoe ALL=(ALL) NOPASSWD: ALL'
        state: present
        validate: 'visudo -cf %s'

    # Remove unused software, open only required ports.
    - name: Remove unused packages.
      package:
        name:
          - nano
          - sendmail
        state: absent

    # File permissions.
    - name: Configure the permissions for the messages log.
      file:
        path: /var/log/messages
        owner: root
        group: root
        mode: 0600

    # Automating updates for RHEL systems.
    - name: Install dnf-automatic.
      yum:
        name: dnf-automatic
        state: present

    - name: Ensure dnf-automatic is running and enabled on boot.
      service:
        name: dnf-automatic-install.timer
        state: started
        enabled: yes

    # Automating updates for Debian systems.
    - name: Install unattended upgrades package.
      apt:
        name: unattended-upgrades
        state: present
      when: ansible_os_family == 'Debian'

    - name: Copy unattended-upgrades configuration files in place.
      template:
        src: "../templates/{{ item }}.j2"
        dest: "/etc/apt/apt.conf.d/{{ item }}"
        owner: root
        group: root
        mode: 0644
      with_items:
        - 20auto-upgrades
        - 50unattended-upgrades
      when: ansible_os_family == 'Debian'

    # Configuring a firewall with `firewalld` on RHEL.
    - name: Ensure firewalld is running.
      service:
        name: firewalld
        state: started

    - name: Configure open ports with firewalld.
      firewalld:
        state: "{{ item.state }}"
        port: "{{ item.port }}"
        zone: external
        immediate: yes
        permanent: yes
      with_items:
        - { state: 'enabled', port: '22/tcp' }
        - { state: 'enabled', port: '80/tcp' }
        - { state: 'enabled', port: '123/udp' }

    # Monitor logins and block suspect IP addresses.
    - name: Ensure EPEL repo is present.
      yum:
        name: epel-release
        state: present
      when: ansible_os_family == 'RedHat'

    - name: Install fail2ban (RedHat).
      yum:
        name: fail2ban
        state: present
        enablerepo: epel
      when: ansible_os_family == 'RedHat'

    - name: Install fail2ban (Debian).
      apt:
        name: fail2ban
        state: present
      when: ansible_os_family == 'Debian'

    - name: Ensure fail2ban is running and enabled on boot.
      service:
        name: fail2ban
        state: started
        enabled: yes

    # Use SELinux (Security-Enhanced Linux).
    - name: Install Python SELinux library.
      yum:
        name: python3-libselinux
        state: present

    - name: Ensure SELinux is enabled in `targeted` mode.
      selinux:
        policy: targeted
        state: enforcing

    - name: Ensure httpd can connect to the network.
      seboolean:
        name: httpd_can_network_connect
        state: yes
        persistent: yes
      when: ansible_selinux.status == 'enabled'

# cat update_rc_tcpip.yml
- name: Update /etc/rc.tcpip
  gather_facts: no
  hosts: ALL

#########################################################################################################
# Latest version date 06/10/2022
#########################################################################################################
# Playbook will comment line "sendmail ..." 
#########################################################################################################

  tasks:

  - name: Comment line begining with time_last_login
    ansible.builtin.lineinfile:
      path: /etc/rc.tcpip
      regexp: '^start /usr/lib/sendmail'
      line: '#start /usr/lib/sendmail "$src_running" "-bd -q${qpi}"'
      backup: yes
      firstmatch: yes
      backrefs: yes
    register: results

  - name: Restart tcpip demon group if file modified
    shell: "/usr/sbin/refresh -g tcpip"
    when: results.changed == true