How can I deploy multiple ssh_key for multiple users on multiple servers with Ansible?

Question

My environment is composed of 2 web servers and 2 db servers.

I have a new developer coming in my team. I need to deploy his ssh key on every server.

He must be able to connect with both user ubuntu and www-data on the web servers and with user ubuntu on the db servers.

My servers are provisioned with Ansible.

How can I do it ?

Answer 1

I solved it by creating a ssh-keys task like so.

In roles/ssh-keys/tasks/main.yml:

---
- name: add authorized key
  authorized_key: user={{ item }} key="{{ lookup('file', 'authorized_keys') }}"
  with_items: authorized_ssh_users
  when: authorized_ssh_users is defined

In roles/ssh-keys/files/authorized_keys:

ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQ[ssh_pub_key_of_dev1] dev1
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQ[ssh_pub_key_of_dev2] dev2
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQ[ssh_pub_key_of_dev3] dev3

In hosts/production:

[webservers]
webserv1-hostname
webserv2-hostname

[webservers:vars]
authorized_ssh_users=['ubuntu','www-data']

[dbservers]
dbserv1-hostname
dbserv2-hostname

[dbservers:vars]
authorized_ssh_users=['ubuntu']

Then in playbook.yml:

- name: Provision ssh keys
  hosts: all
  sudo: true
  roles:
  - ssh-keys

With this solution, I can manage every combination of server / user to deploy key on.