Use this playbook if you want to improve the security of your server and want to :

• change root password
• add admin user of your choice
• add authorized keys for admin user
• add admin user in sudoers
• install default packages (ufw, fail2ban, ...)
• install user extra packages
• setup firewall
• disallow password authentication
• disallow root SSH access

edit personal information in secrets.yml ansible vault (default password: password)

mv secrets.default secrets.yml
ansible-vault rekey secrets.yml
ansible-vault edit secrets.yml

run (replace <SUDOER>, <SSH_PRIVATE_KEY>, <IP>)

ansible-playbook -u <SUDOER> --private-key=<SSH_PRIVATE_KEY> --ask-become-pass  --ask-vault-pass -i '<IP>,' bootstrap.yml

• ansible 2+
• git

git clone https://github.com/guillaumevincent/Ansible-My-First-5-Minutes-On-A-Server
cd Ansible-My-First-5-Minutes-On-A-Server

verify that you can ping your server via ssh

ansible all --user=<SUDOER> --private-key=<SSH_PRIVATE_KEY> --inventory-file='<IP>,' -m ping

example on a raspberry pi :

ansible all --user=pi --private-key=~/.ssh/id_rsa --inventory-file='192.168.1.100,' -m ping

192.168.1.100 | SUCCESS => {
    "changed": false,
    "ping": "pong"
}

explanations :

• ansible all : run ansible command on all hosts
• --user=pi : ssh with user pi
• --private-key=~/.ssh/id_rsa : path of the ssh key use to connect to the server
• --inventory-file='192.168.1.100,' : specify inventory file. do not forget the comma ,
• -m ping : run module ping

if the previous command failed, <SUDOER> don't have access

All your personal information is stored in an encrypted file with ansible-vault.

move secrets.default to secrets.yml

mv secrets.default secrets.yml

change your vault password (existing password: password)

ansible-vault rekey secrets.yml

follow the instructions to change ansible vault password

Vault password: password
New Vault password: <YOUR_VAULT_PASSWORD>
Confirm New Vault password: <YOUR_VAULT_PASSWORD>
Rekey successful

edit secrets information

ansible-vault edit secrets.yml

the encrypted information that you need to change :

---
ROOT_PASSWORD: 'xxxxxx'
ADMIN_PASSWORD: 'xxxxxx'
ADMIN_USERNAME: admin
PUBLIC_KEYS:
  - ~/.ssh/id_rsa.pub
#EXTRA_PACKAGES:
#  - vim
#  - htop

now run bootstrap.yml file

ansible-playbook --user=<SUDOER> --private-key=<SSH_PRIVATE_KEY> --ask-become-pass  --ask-vault-pass --inventory-file='<IP>,' bootstrap.yml

example

ansible-playbook --user=pi --private-key=~/.ssh/id_rsa --ask-become-pass --ask-vault-pass --inventory-file='192.168.1.100,' bootstrap.yml

change the --inventory-file parameter

ansible-playbook .... --inventory-file='<IP>,<IP2>,<IP3>,' bootstrap.yml

You need ssh access to use ansible. If you have the password of a sudoer, then copy your ssh public key on your server.

ssh-copy-id -i ~/.ssh/id_rsa.pub <SUDOER>@<IP>

I thought it was a good idea. But running SSH on a port over 1024 (i.e. a non-privileged port) is actually potentially a security vulnerability. Imagine you run SSH on port 2222 and your ssh daemon crashes. Now any local user can start their own (fake) ssh daemon on port 2222 which could be bad.

See why it's probably better to stay on port 22 Should I change the default SSH port on linux servers?

Thanks Cryonine