1. What is ansible?

https://docs.ansible.com/

https://en.wikipedia.org/wiki/Ansible_(software)

 

2. Ansible commands for this and that

In no particular order.

 

2.1. Test run a playbook file

# ansible-playbook playbook.file.yml --check

 

2.2. Ad-hoc command

Run the command on all members in group centos. For CentOS this is set in /etc/ansible/hosts.

# ansible centos -a 'yum update -y'

 

2.3. Specify target groups in playbook

Specifying the below in the playbook, will run the commands on the two host groups centos-cli and centos-srv.

- hosts: centos-cli:centos-srv

Source: https://github.com/ansible/ansible/issues/3546#issuecomment-21024596

 

2.4. Create multiple users on multiple computers and distribute ssh-keys

See these:

http://ciscostuff.gurjap.org/user-ansible-create-multiple-users-authorize-ssh-keys

https://groups.google.com/forum/#!topic/ansible-project/t6dsaaxtTyo

https://www.howtoforge.com/tutorial/setup-new-user-and-ssh-key-authentication-using-ansible/

Variation with sudo privileges:

https://github.com/msergiy87/ansible-create-users.

 

2.5. Considerations when creating ssh key-pairs

https://serverfault.com/questions/910071/how-to-generate-host-ssh-keys-via-ansible

 

2.6. Run tasks step by step

Sometimes you don't want to run all tasks in a playbook. Should this be the case you can use the --step flag.

# playbook.yml
- hosts: centos-cli   tasks:     - name: first task       # run some task      - name: second task      # run some other task
# ansible-playbook playbook.yml --step  > Perform task: first task (y/n/c): n ... > Perform task: second task (y/n/c): y #

 Source: http://codeheaven.io/15-things-you-should-know-about-ansible/

 

2.7. Using playbook debugger for logging per playbook

https://stackoverflow.com/questions/35135954/how-to-log-in-a-separate-file-per-playbook-in-ansible

https://groups.google.com/forum/#!msg/ansible-project/ql6xFaTDcYw/UwdkDuP7BQAJ

https://docs.ansible.com/ansible/latest/user_guide/playbooks_debugger.html

https://docs.ansible.com/ansible/latest/plugins/callback/log_plays.html

This notelett is a work in progress. Need to do some reading...

 

 

3. Sources

Various sources on the internet. See info inline above.