Ansible - Basics

You will want a user and ssh key on every host.

You will want to start out by creating an inventory file.

Example inventory file:

/etc/ansible/hosts

192.0.3.25
server1.lab.net
server2.lab.net

You can ping all hosts in inventory with this command:

ansible all -m ping

Another test:

ansible all -a "/bin/echo Hello World"

Basic playbook example:

test-task1.yaml

---
- name: A Test Playbook
  hosts: all
  tasks:
     - name: First Test
       command: "touch /home/user1/testing.txt"

Running a playbook:

ansible-playbook mytask.yaml

Using the ping module and sudo:

ansible all -m ping -u user1                              # specify user
ansible all -m ping -u user1 --become                     # sudo to root
ansible all -m ping -u user1 --become --become-user admin # sudo to admin

Ad hoc commands:

ansible group1 -a "/sbin/reboot"            # as current user
ansible group1 -a "/sbin/reboot" -f 10    # as current user, 10 parallel forks  
ansible group1 -a "/sbin/reboot" -f 10 -u username   # as this user
ansible group1 -a "/sbin/reboot" -f 10 -u username --become  # as this user, then sudo to root
ansible group1 -a "/sbin/reboot" -f 10 -u username --become --ask-become-pass # ask sudo password
ansible group1 -a "/sbin/reboot" -f 10 -u username --become --K        # .

Shell module:

• can use pipes and redirects
• be careful quoting variables

ansible group2 -m ansible.builtin.shell -a 'echo test > output.txt'

ansible group2 -m ansible.builtin.copy -a “src=/etc/hosts dest=/tmp/hosts”

Permissions / ownership:

ansible webservers -m ansible.builtin.file -a "dest=/srv/foo/a.txt mode=600"
ansible webservers -m ansible.builtin.file -a "dest=/srv/foo/b.txt mode=600 owner=mdehaan group=mdehaan"

Create directory:

ansible webservers -m ansible.builtin.file -a "dest=/path/to/c mode=755 owner=mdehaan group=mdehaan state=directory"

Delete recursively:

ansible webservers -m ansible.builtin.file -a "dest=/path/to/c state=absent"

Install without updating:

ansible webservers -m ansible.builtin.yum -a "name=acme state=present"

Ensure specific version is installed:

ansible webservers -m ansible.builtin.yum -a "name=acme-1.5 state=present"

Latest version:

ansible webservers -m ansible.builtin.yum -a "name=acme state=latest"

Ensure package is not installed:

ansible webservers -m ansible.builtin.yum -a "name=acme state=absent"

Users:

ansible all -m ansible.builtin.user -a "name=foo password=<crypted password here>"
ansible all -m ansible.builtin.user -a "name=foo state=absent"

Ensure started, stopped, restarted:

ansible webservers -m ansible.builtin.service -a "name=httpd state=started"
ansible webservers -m ansible.builtin.service -a "name=httpd state=restarted"
ansible webservers -m ansible.builtin.service -a "name=httpd state=stopped"

See all facts:

ansible all -m ansible.builtin.setup