Secure MQTT & OTA VPS Deployment
Budget: $30 – $250 CAD
I’m spinning up a fresh Ubuntu VPS and need it turned into a rock-solid hub for my IoT fleet. The box must host two main services—Mosquitto for messaging and a Mender server for over-the-air firmware updates—without compromising security, performance, or future maintainability.
Here’s the picture
• Mosquitto will run behind TLS with mutual authentication. I’ll give you the root CA; you generate and stage broker and client certs so the standard mosquitto_pub / mosquitto_sub TLS test passes.
• Mender must be installed in its open-source edition, set to distribute only signed artifacts. I already sign firmware; the server simply has to enforce signature checking before rollout.
• fail2ban on the host should block any source IP after three bad login or certificate failures (SSH, Mosquitto, and Mender’s API).
• Everything lives on the same VPS yet stays logically isolated—Docker or systemd-managed services are fine as long as configuration remains readable and easy to back up.
• Firewall rules (UFW or iptables) expose only the essentials: 8883 for MQTT, 443 for Mender/HTTPS, and 22 for SSH.
• I want clean deployment scripts or a single docker-compose.yml so I can rebuild the environment in minutes.
Acceptance checks
1. A shell script or compose stack that fully provisions Mosquitto and Mender on a clean Ubuntu image.
2. Successful TLS publish/subscribe test using provided client certificates.
3. Firmware upload and deployment from Mender’s UI to a test device, rejected when the artifact is unsigned.
4. Three consecutive failed SSH or MQTT logins trigger a ban, confirmed with fail2ban-client status.
5. A concise README covering rebuild steps, backup locations, and how to rotate certificates.
If this sounds like your kind of infrastructure task, let’s lock it in and get the devices talking safely.
Here’s the picture
• Mosquitto will run behind TLS with mutual authentication. I’ll give you the root CA; you generate and stage broker and client certs so the standard mosquitto_pub / mosquitto_sub TLS test passes.
• Mender must be installed in its open-source edition, set to distribute only signed artifacts. I already sign firmware; the server simply has to enforce signature checking before rollout.
• fail2ban on the host should block any source IP after three bad login or certificate failures (SSH, Mosquitto, and Mender’s API).
• Everything lives on the same VPS yet stays logically isolated—Docker or systemd-managed services are fine as long as configuration remains readable and easy to back up.
• Firewall rules (UFW or iptables) expose only the essentials: 8883 for MQTT, 443 for Mender/HTTPS, and 22 for SSH.
• I want clean deployment scripts or a single docker-compose.yml so I can rebuild the environment in minutes.
Acceptance checks
1. A shell script or compose stack that fully provisions Mosquitto and Mender on a clean Ubuntu image.
2. Successful TLS publish/subscribe test using provided client certificates.
3. Firmware upload and deployment from Mender’s UI to a test device, rejected when the artifact is unsigned.
4. Three consecutive failed SSH or MQTT logins trigger a ban, confirmed with fail2ban-client status.
5. A concise README covering rebuild steps, backup locations, and how to rotate certificates.
If this sounds like your kind of infrastructure task, let’s lock it in and get the devices talking safely.