Script shell to start the playbook

# cat /Ansible-Playbook/scripts/cron_download_files.sh

#!/bin/bash
# Start playbook to download files
unset http_proxy
unset https_proxy

log="/var/log/ansible/$1.log"
playbook='download_file.yml'

cd ~/download
>> /var/log/ansible/$1.log
date >> /var/log/ansible/$1.log
>> /var/log/ansible/$1.log
ansible-playbook -vvvv $playbook >> /var/log/ansible/$1.log

# message monitoring
case $? in
  0)  status="0"
      message="Success - script:$playbook log:$log"   ;;
  99) status="2"
      message="Error : User interrupted execution - script:$playbook log:$log"   ;;
  *)  status="2"
      message="Error - script:$playbook log:$log"   ;;
esac

server=nagiossrv01
echo "$(hostname -s);ansible_download;$status;$message" | /usr/local/nagios/bin/send_nsca -H $server -p 5667 -c /usr/local/nagios/etc/send_nsca.cfg -d ";"

Into ~/download

# ls -lsa ~/download

ansible.cfg
.vaultPwd.yml   --> password clear for vault
download_file.yml

# cat ansible.cfg | grep -v '^#' | sed '/^$/d'
[defaults]
inventory = ~/inventory/inventory_download
host_key_checking = False
retry_files_enabled = False
pipelining = True
ansible_python_interpreter = /usr/bin/python3
inventory_plugins = ~/.ansible/collections/ansible_collections/xxxxx
log_path=/var/log/ansible/stdout.log
vault_password_file=./.vaultPwd.yml
forks = 15
ansible_ssh_extra_args='-C -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null'
[inventory]
enabled_plugins = xxxxx
[privilege_escalation]
become = True
become_method = sudo
become_user = ansibuser


# cat ~/inventory/inventory_download
[linux]
linux01
linux02

Execute only one role

ansible-playbook setup.yml -i inventory.ini --tags "common"

setup.yml

---
- hosts: prod
  vars_files:
    - group_vars/all.yml
    - group_vars/main.yml
    - group_vars/docker.yml
    - group_vars/monit.yml
    - group_vars/networking.yml
    - group_vars/vault.yml
  user: "{{default_username}}"  # run whole script with default user
  become: yes
  roles:  # order is not random!
    - role: nickjj.fail2ban
      tags: fail2ban
    - role: common
      tags: common
    - role: ufw
      tags: ufw
    - role: user
      tags: user
    - role: ssh
      tags: ssh
    - role: nickjj.docker
      when: install_docker == true
      tags: docker
    - role: docker
      when: install_docker == true
      tags: docker
    - role: jnv.debian-backports
      tags: common
    - role: ansible-monit
      tags: common
    - role: jnv.unattended-upgrades
      tags: common
    - role: networking
      tags: networking
    - role: reboot
      tags: reboot

cat group_vars/main.yml

sshpub_location: SSH_PUBKEY_HERE #the full path to your SSH public key ( e.g. /Users/username/.ssh/id_ed25519.pub )
root_pw: "PASSWORD_HERE" #root password that should be set
user_name: USERNAME_HERE #username for the created user
user_pw: "PASSWORD_HERE" #password for the new user
ssh_port: 55899 #port number for ssh
mail_to: mailto@example.com #the mail address where mails should be sent to
mail_from: mailfrom@example.com #the mail address where mails are sent from 
mail_smtp_server: smtp.example.com #mail server, e.g. smtp.gmail.com
mail_pw: PASSWORD_HERE #password for the mail_from mail address
mail_port: 587 #the port where mails are sent to the mail server, e.g. 587

cat group_vars/all.yml

---
# general settings
default_username: debian
dot_forward_email: <YOUR_EMAIL_GOES_HERE>
private_key: .ssh/id_rsa
public_key: .ssh/id_rsa.pub
ntpserver: pool.ntp.org
timezone: Europe/Rome

# default sshd port
sshd_port: 22

# generate random passwords for default user and root user
default_password: "{{lookup('password', '/dev/null length=15 chars=ascii_letters,digits,punctuation')}}"
root_password: "{{lookup('password', '/dev/null length=15 chars=ascii_letters,digits,punctuation')}}"

# unattended packages install configuration
unattended_mail: "{{dot_forward_email}}"
unattended_remove_unused_dependencies: true
unattended_automatic_reboot_time: "03:00"
unattended_update_days: "Sat"
unattended_clean_interval: 7

# fail2ban
fail2ban_loglevel: INFO
fail2ban_services:
  - name: ssh
    port: ssh
    filter: sshd
    logpath: /var/log/auth.log

cat roles/ssh/tasks/main.yml

    - name: secure ssh configuration 
      become: true
      blockinfile:
        path: /etc/ssh/sshd_config
        block: |
          ########################################################################################################
          # start settings from https://infosec.mozilla.org/guidelines/openssh#modern-openssh-67 as of 2019-01-01
          ########################################################################################################
          # Supported HostKey algorithms by order of preference.
          HostKey /etc/ssh/ssh_host_ed25519_key
          HostKey /etc/ssh/ssh_host_rsa_key
          HostKey /etc/ssh/ssh_host_ecdsa_key
          KexAlgorithms curve25519-sha256@libssh.org,ecdh-sha2-nistp521,ecdh-sha2-nistp384,ecdh-sha2-nistp256,diffie-hellman-group-exchange-sha256
          Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr
          MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,umac-128@openssh.com
          # LogLevel VERBOSE logs user's key fingerprint on login. Needed to have a clear audit track of which key was using to log in.
          LogLevel VERBOSE
          # Use kernel sandbox mechanisms where possible in unprivileged processes
          # Systrace on OpenBSD, Seccomp on Linux, seatbelt on MacOSX/Darwin, rlimit elsewhere.
          # Note: This setting is deprecated in OpenSSH 7.5 (https://www.openssh.com/txt/release-7.5)
          # UsePrivilegeSeparation sandbox
          ########################################################################################################
          # end settings from https://infosec.mozilla.org/guidelines/openssh#modern-openssh-67 as of 2019-01-01
          ########################################################################################################
          # don't let users set environment variables
          PermitUserEnvironment no
          # only use the newer, more secure protocol
          Protocol 2
          # disable port forwarding
          AllowTcpForwarding no
          AllowStreamLocalForwarding no
          GatewayPorts no
          PermitTunnel no
          # don't allow login if the account has an empty password
          PermitEmptyPasswords no
          # ignore .rhosts and .shosts
          IgnoreRhosts yes
          # verify hostname matches IP
          UseDNS yes
          Compression no
          TCPKeepAlive no
          AllowAgentForwarding no
          # don't allow .rhosts or /etc/hosts.equiv
          HostbasedAuthentication no
      notify: restart ssh service

    - name: secure ssh configuration part 2
      become: true
      lineinfile:
        dest: /etc/ssh/sshd_config
        regexp: "{{ item.regexp }}"
        line: "{{ item.line }}"
      loop:
        - { regexp: '^AllowGroups', line: 'AllowGroups sshusers' }
        - { regexp: '^ClientAliveCountMax', line: 'ClientAliveCountMax 0'}
        - { regexp: '^ClientAliveInterval', line: 'ClientAliveInterval 300'}
        - { regexp: '^ListenAddress', line: 'ListenAddress 0.0.0.0'}
        - { regexp: '^LoginGraceTime', line: 'LoginGraceTime 30'}
        - { regexp: '^MaxAuthTries', line: 'MaxAuthTries 2'}
        - { regexp: '^MaxSessions', line: 'MaxSessions 2'}
        - { regexp: '^MaxStartups', line: 'MaxStartups 2'}
        - { regexp: '^PasswordAuthentication', line: 'PasswordAuthentication no'}
        - { regexp: '^Port', line: 'Port {{ ssh_port }}'}
        - { regexp: '^PermitRootLogin', line: 'PermitRootLogin no'}
        - { regexp: '^X11Forwarding', line: 'X11Forwarding no'}
        - { regexp: '^Subsystem', line: 'Subsystem sftp  internal-sftp -f AUTHPRIV -l INFO'}
      notify: restart ssh service

    - name: remove short diffie diffie-hellman
      become: true
      shell: |
        awk '$5 >= 3071' /etc/ssh/moduli | sudo tee /etc/ssh/moduli.tmp
        mv /etc/ssh/moduli.tmp /etc/ssh/moduli
      notify: restart ssh service

cat roles/ssh/handlers/main.yml

    - name: restart ssh service
      become: yes
      service: 
        name: ssh
        state: restarted

cat roles/others/tasks/main.yml

- name: include Debian.yml
  include_tasks: Debian.yml
  when: ansible_os_family == 'Debian'
- name: include RedHat.yml
  include_tasks: RedHat.yml
  when: ansible_os_family == 'RedHat'

cat roles/others/tasks/Debian.yml

- name: install others
  apt:
    name: ['bash-completion', 'htop', 'rsync', 'tmux', 'nmap', 'netcat-openbsd', 'gawk']
    state: present
  when: ansible_os_family == 'Debian'

cat roles/others/tasks/Redhat.yml

- name: install others
  yum: name={{ item }} state=present
  when: ansible_os_family == 'Redhat'
  with_items:
    - bash-completion
    - tig
    - wget
    - htop
    - rsync
    - tmux
    - nmap
    - nmap-ncat

File is backuped with format 2025-02-23T14:30:00Z

---
- name: Backup file if it exists
  hosts: localhost
  tasks:
    - name: Check if the file exists
      stat:
        path: /path/to/your/file
      register: file_stat

    - name: Create a backup if the file exists
      copy:
        src: /path/to/your/file
        dest: "/path/to/backup/file_{{ ansible_date_time.iso8601 }}.bak"
        remote_src: yes
      when: file_stat.stat.exists

Backup only if modified

---
- name: Backup file if it is different
  hosts: localhost
  tasks:
    - name: Get the checksum of the current file
      stat:
        path: /path/to/your/file
      register: file_stat

    - name: Get the checksum of the last backup (if exists)
      stat:
        path: "/path/to/backup/file_last.bak"
      register: backup_stat
      ignore_errors: yes

    - name: Compare the current file checksum with the backup checksum
      command: "sha256sum /path/to/your/file | awk '{ print $1 }'"
      register: current_checksum
      when: file_stat.stat.exists

    - name: Compare the backup checksum (if backup exists)
      command: "sha256sum /path/to/backup/file_last.bak | awk '{ print $1 }'"
      register: backup_checksum
      when: backup_stat.stat.exists

    - name: Backup the file if checksums are different
      copy:
        src: /path/to/your/file
        dest: "/path/to/backup/file_{{ ansible_date_time.iso8601 }}.bak"
        remote_src: yes
      when: 
        - file_stat.stat.exists
        - (backup_stat.stat.exists == false or current_checksum.stdout != backup_checksum.stdout)

---
- name: Insert line after pattern using bash
  hosts: all
  become: true
  tasks:
    - name: Insert line after pattern using sed
      shell: |
        if ! grep -q '^new_config_line=value$' /etc/example.conf; then
          sed -i '/# INSERT HERE/a new_config_line=value' /etc/example.conf
        fi
      args:
        executable: /bin/bash

https://stackoverflow.com/questions/70162334/in-ansible-how-do-i-add-a-line-without-delete-comment

https://www.theunixschool.com/2012/06/insert-line-before-or-after-pattern.html