Ansible initial setup

ansible-install | ansible | ansible-ntp | ansible-rhel

requirements

make sure you’ve set up SSH without a password from the ansible system towards the target systems

install

and if you want Slack notifications

apt install python3-prettytable

manual inventory

define hosts and groups to operate

cd /etc/ansible/

mv -i ansible.cfg ansible.cfg.dist
mv -i hosts hosts.dist

ansible-config init --disabled -t all > ansible.cfg.defaults.plugins
ansible-config init --disabled > ansible.cfg.defaults

get rid of the warning

vi ansible.cfg

[defaults]
collections_paths = /usr/share/ansible_collections
interpreter_python = auto_silent
remote_tmp = /tmp
timeout = 3

# v2.17+
#result_format = yaml

# v2.16
stdout_callback = community.general.yaml
deprecation_warnings = false

[connection]
pipelining = true

[ssh_connection]
# use client config and enable persistent sessions
ssh_args = -F /home/gitlab-runner/.ssh/config -o controlmaster=auto -o controlpersist=15m
#ssh_args = -F /home/USER/.ssh/config -o controlmaster=auto -o controlpersist=15m

[docker_connection]
timeout = 3

more options

#stdout_callback = minimal
#callback_whitelist=ansible.posix.timer,ansible.posix.profile_tasks,ansible.posix.profile_roles
#callbacks_enabled=ansible.posix.timer,ansible.posix.profile_tasks,ansible.posix.profile_roles

you might require those additional module collections

for collection in community.general \
    ansible.posix \
    community.docker; do
    ansible-galaxy collection install \
        -fiUp /usr/share --force-with-deps \
        $collection
done; unset collection

and if you need to upgrade one of those at some point e.g.

ansible-galaxy collection install --upgrade community.docker

setup your host groups – assuming ~/.ssh/config is alright

mkdir ~/dev/ansible/playbooks/
cd ~/dev/ansible/playbooks/

vi hosts

[servers]
HOST
HOST
...

[servers:vars]
become=false
timezone=Europe/Moscow
country_code=ru

[stations]
HOST        ansible_connection=local

[stations:vars]
become=false
timezone=Europe/Moscow
country_code=ru

if we were to use FQDN:PORT instead without ~/.ssh/config, then

#FQDN:PORT ansible_user=root

check

ansible all --list-hosts

make sure your ssh client knows the fingerprints

ssh HOST
#ssh HOST -p PORT -l root

ready to go

as user

ls -alhF ~/.ssh/config

check accessiblity of the managed systems

ansible all -m ping

send raw commands without using Python on the remote host e.g.

ansible all -m raw -a hostname

send shell commands using Python on the remote host e.g.

ansible all -m shell -a hostname

or print a remote variable e.g.

ansible all -m shell -a 'echo $TERM'

restart nginx on a specific host – beware json output is awefully long

ansible HOST -m service -a "name=nginx state=restarted"

you can now proceed with playbooks

additional notes

inter-operatbility

if you are using ClusterIt aside Ansible, this script might be useful to maintain a shared list of hosts across both tools

echo -n converting clusterit.conf to ansible hosts file...
sed 's/GROUP:\(.*\)/\[\1\]/' /etc/clusterit.conf > /etc/ansible/hosts && echo done

resources

http://docs.ansible.com/ansible/intro_getting_started.html

http://docs.ansible.com/ansible/intro_configuration.html

http://docs.ansible.com/ansible/playbooks_conditionals.html

https://serversforhackers.com/an-ansible-tutorial

http://blog.programster.org/ansible-run-a-local-script-on-remote-server/

Ansible change ssh port in playbook https://stackoverflow.com/questions/34333058/ansible-change-ssh-port-in-playbook

https://stackoverflow.com/questions/28553307/ansible-using-custom-ssh-config-file

https://redhat.com/en/blog/faster-ansible-playbook-execution

https://wearenotch.com/speed-up-ansible-playbook-execution/