🔒 Certificates¶

Web certificates are managed using Certbot, a widely used tool for obtaining trusted SSL/TLS certificates from Let’s Encrypt.
Certificates are staged inside the reverse proxy server under /data/certs, with a dedicated folder for each host.
Automation is handled via Ansible playbooks, ensuring consistency and repeatability across environments.

⚙️ Certificate Generation¶

Certificates are generated using the Ansible playbook:

playbooks/certs/generate_certs.yml

• The Certbot/Let’s Encrypt working directory is located at /data/letsencrypt on the host defined in the [certs] inventory group.
• This is typically the main reverse proxy host.
• The playbook uses the rproxy_setup_sites list variable to determine which hostnames to pass to Certbot.
• The server_name field defines the hostname for certificate generation.
• Multiple sites can be specified in the inventory when required.

Example Configuration¶

rproxy_setup_sites:
  - server_name: homelab.refol.us
    port: 80
    proxy_pass: "http://{{ global_ip_addresses['redmine-0'] }}"
    allow_list:
      - 192.168.0.0/24
      - 192.168.2.0/24
      - 24.105.250.200
      - 70.107.117.124
    restricted: false

💡 This configuration allows Certbot to generate certificates for homelab.refol.us while enforcing access controls via the allow_list.

📂 Certificate Staging¶

Once generated, certificates are staged using:

playbooks/certs/stage_certs.yml

This playbook copies the following files from the Let’s Encrypt folder into the appropriate host folder under /data/certs:

• privkey.pem → Private key
• fullchain.pem → Full certificate chain

These files are then referenced in the NGINX site configuration:

ssl_certificate     /data/certs/homelab.refol.us/fullchain.pem;
ssl_certificate_key /data/certs/homelab.refol.us/privkey.pem;

✅ Staging ensures certificates are consistently deployed and referenced by reverse proxy configurations.

🧪 Example Workflow¶

To generate and stage certificates for homelab.refol.us:

INV=inventory/redmine/inventory.ini
ansible-playbook -i $INV playbooks/certs/generate_certs.yml -k
ansible-playbook -i $INV playbooks/certs/stage_certs.yml -k

🛠️ Debugging Certificate Request Errors¶

If errors occur during certificate generation or renewal:

• Review the Let’s Encrypt log file on the reverse proxy host (rproxy-0):

  /data/letsencrypt/log/letsencrypt.log
  

• Common issues include:
  • DNS misconfiguration (hostname not resolving correctly).
  • Firewall restrictions blocking port 80/443.
  • Incorrect server_name values in the playbook.

✅ Summary¶

This workflow provides a fully automated certificate lifecycle:

• Generation via Ansible + Certbot.
• Staging into /data/certs for each host.
• Integration with NGINX for secure HTTPS delivery.
• Debugging via centralized Let’s Encrypt logs.

Together, these practices ensure secure, maintainable, and repeatable certificate management across the homelab environment.