Ansible playbooks for setting up Ubuntu 18.04/16.04 servers as neo nodes:

• Basic server security setup
• neo-cli nodes and notification servers
  • supervised and auto-started by systemd
  • Script to check increasing block-height, which restarts the service if it is stuck
• Nginx reverse proxy with IP rate-limit and caching, CORS, logging and logrotate
• Let's Encrypt certificates with auto-renewals
• Playbooks for upgrading nodes

Playbooks

• server_base_setup.yml: Security, user, software, unattended updates. Only incoming port allowed is 22. Note: Disables SSH login as root user.
• neo_node_base.yml: Basic neo-cli setup, bootstrap if available. No other open ports to the outside.
• neo_node_notif_base.yml: Basic notification-server setup, bootstrap if available. No other open ports to the outside.
• neo_node_nginx.yml: Nginx reverse proxy, 10s caching, Let's Encrypt certificate w/ auto renewal. Opens ports 80 and 443.
• neo_node_upgrade.yml: Update neo nodes (only works if the old chain compatible)
• neo_node_notif_upgrade.yml: Update neo nodes (only works if the old chain compatible)

After the basic server setup, you'll need to enable 2FA with google authenticator manually as described here. Also, use your YubiKey protected SSH key for login. See also here for more infos.

Notes

• All custom software and scripts are located in /server/ (configurable in group_vars/all.yml)
• Tested with ansible 2.6.1+
• Can be easily tested with a VM (Vagrantfile is included)
• Servers are based on Ubuntu 18.04 LTS (Bionic Beaver) 64 bit or Ubuntu 16.04
  • Note: the latest Ubuntu version does not include Python 2 anymore, only /usr/bin/python3, so we configure that in inventory
• See also:
  • https://github.com/CityOfZion/standards/blob/master/nodes.md

Getting Started

The easiest start is to run the playbooks on a virtual machine. Included is a Vagrantfile which spins up an Ubuntu instance with the IP 10.0.0.10 that you can use to experiment. If you want to change that IP, just update Vagrantfile and inventory and recreate the VM.

Code overview:

• General variables are in group_vars/*.yml
• The playbooks are in playbooks/*.yml
• The inventory lists your servers and defines the groups. See inventory
• Files and templates that are uploaded to the server can be found in the respective directories

Running on a new server

Add the server(s) to inventory (perhaps remove the existing ones). If you want the Let's Encrypt/nginx setup, then use the FQDN in the inventory file rather than the IP address, as this is used for getting the certificates (alternatively, you can override this with a fqdn variable in host_vars/<ip>.yml. Then run the playbooks on all hosts like this:

$ ansible-playbook -i inventory playbooks/server_base_setup.yml
$ ansible-playbook -i inventory playbooks/node_neo_base.yml

If you want to provision the server with notification server instead of standard neo-cli:

$ ansible-playbook -i inventory playbooks/node_neo_notif_base.yml

You can also limit it to a specific host, or to a full group like node_neo:

$ ansible-playbook -i inventory --limit node_neo playbooks/server_base_setup.yml
$ ansible-playbook -i inventory --limit node_neo playbooks/node_neo_base.yml

After neo-cli is setup, the server is running it with a systemd service called neonode. You can check the neo-cli node inside the server:

server$ systemctl status neonode
server$ journalctl -f -u neonode

Finally, run the nginx+letsencrypt playbook:

$ ansible-playbook -i inventory --limit node_neo playbooks/node_neo_nginx.yml

Now you can do HTTPS request to the server.

Updating nginx config

If you want to update the nginx config, just change the template file, and re-run playbooks/node_neo_nginx.yml.

Testing with Vagrant

Start the VM:

$ vagrant up

Test connectivity by running the ansible ping module:

$ ansible -i inventory vm --limit 10.0.0.10 -m ping

Run the playbooks:

$ ansible-playbook -i inventory --limit 10.0.0.10 playbooks/server_base_setup.yml
$ ansible-playbook -i inventory --limit 10.0.0.10 playbooks/node_neo_base.yml

SSH into the VM:

$ vagrant ssh

Inside the VM you can check the nginx proxy or the neo-cli service (neonode):

vagrant$ systemctl status neonode
vagrant$ systemctl start|stop|restart neonode

Destroy the VM and remove all content:

$ vagrant destroy