Ansible is an incredible configuration management and provisioning utility that enables you to automate all the things. In this series, you’ll learn everything you need to know in order to use Ansible for your day-to-day administration duties.

site.yml (new version)

 ---
 
 - hosts: all
   become: true
   pre_tasks:
 
   - name: update repository index (CentOS)
     tags: always
     dnf:
       update_cache: yes
     changed_when: false
     when: ansible_distribution == "CentOS"
 
   - name: update repository index (Ubuntu)
     tags: always
     apt:
       update_cache: yes
     changed_when: false
     when: ansible_distribution == "Ubuntu"
 
 - hosts: all
   become: true
   roles:
     - base
    
 - hosts: workstations
   become: true
   roles:
     - workstations
 
 - hosts: web_servers
   become: true
   roles:
     - web_servers
 
 - hosts: db_servers
   become: true
   roles:
     - db_servers
 
 - hosts: file_servers
   become: true
   roles:
     - file_servers

Create a roles directory

 mkdir roles

Create a directory for each role you wish to add:

 cd roles
 mkdir base
 mkdir db_servers
 mkdir file_servers
 mkdir web_servers
 mkdir workstations

Inside each role directory, create a tasks directory

 cd <role_name>
 mkdir tasks

main.yml (base role)

Note: Use your actual key below on the last line, in place of the one you see here.

 - name: add ssh key for simone
   authorized_key:
     user: simone
     key: "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIAe7/ofWLNBq3+fRn3UmgAizdicLs9vcS4Oj8VSOD1S/ ansible"

Set up required files/folders for db_servers role

 cd ..
 cd ..
 mkdir db_servers
 cd db_servers
 mkdir tasks
 cd tasks
 vim main.yml

main.yml (db_servers role)

 - name: install mariadb server package (CentOS)
   tags: centos,db,mariadb
   dnf:
     name: mariadb
     state: latest
   when: ansible_distribution == "CentOS"
 
 - name: install mariadb server
   tags: db,mariadb,ubuntu
   apt:
     name: mariadb-server
     state: latest
   when: ansible_distribution == "Ubuntu"

main.yml (file_servers role)

 - name: install samba package
   tags: samba
   package:
     name: samba
     state: latest

main.yml (workstations role)

 - name: install unzip
   package:
     name: unzip
 
 - name: install terraform
   unarchive:
     src: https://releases.hashicorp.com/terraform/0.12.28/terraform_0.12.28_linux_amd64.zip
     dest: /usr/local/bin
     remote_src: yes
     mode: 0755
     owner: root
     group: root

main.yml (web_servers role)

 - name: install httpd package (CentOS)
   tags: apache,centos,httpd
   dnf:
     name:
       - httpd
       - php
     state: latest
   when: ansible_distribution == "CentOS"
 
 - name: start and enable httpd (CentOS)
   tags: apache,centos,httpd
   service:
     name: httpd
     state: started
     enabled: yes
   when: ansible_distribution == "CentOS"
 
 - name: install apache2 package (Ubuntu)
   tags: apache,apache2,ubuntu
   apt:
     name:
       - apache2
       - libapache2-mod-php
     state: latest
   when: ansible_distribution == "Ubuntu"
 
 - name: change e-mail address for admin
   tags: apache,centos,httpd
   lineinfile:
     path: /etc/httpd/conf/httpd.conf
     regexp: '^ServerAdmin'
     line: ServerAdmin somebody@somewhere.net
   when: ansible_distribution == "CentOS"
   register: httpd
 
 - name: restart httpd (CentOS)
   tags: apache,centos,httpd
   service:
     name: httpd
     state: restarted
   when: httpd.changed    
 
 - name: copy html file for site
   tags: apache,apache,apache2,httpd
   copy:
     src: default_site.html
     dest: /var/www/html/index.html
     owner: root
     group: root
     mode: 0644

Run the new playbook

 ansible-playbook site.yml