TCP port 9093 is primarily used by **Prometheus**, an open-source monitoring and alerting system.
Port 9093 serves as the default port for various components within the Prometheus ecosystem, including the Prometheus server itself and potentially other related services like Alertmanager. It's the port where these services listen for connections, often to expose metrics, receive alerts, or communicate with other parts of the system.
According to the provided reference, TCP port 9093 is commonly utilized by Prometheus. It's crucial to understand that **ensuring there is no unrestricted inbound access to this port is important**. This is because such unrestricted access could potentially allow unauthorized access to the Prometheus server and sensitive data it collects or manages.
Here's a quick summary:
| Port | Protocol | Primary Use | Associated Application | Security Concern |
| :--- | :------- | :------------------ | :--------------------- | :-------------------------------- |
| 9093 | TCP | Monitoring/Alerting | Prometheus | Unrestricted inbound access risk |
## Why is Port 9093 Relevant for Prometheus?
Prometheus operates by collecting metrics from configured targets at given intervals, evaluating rule expressions, displaying the results, and triggering alerts if conditions are met. Port 9093 facilitates key functions, such as:
* **Server API/Web UI:** The Prometheus server often exposes its web user interface and API on this port, allowing users to query metrics, view graphs, and manage configurations.
* **Alerting:** While Alertmanager typically uses port 9093 for its own API/UI, the Prometheus server communicates with Alertmanager (often on port 9093 or 9094, depending on configuration) to send alert notifications.
## Security Considerations for Port 9093
Given that port 9093 can expose the Prometheus server's interface, metrics, and configuration, security is paramount. As highlighted by the reference:
* **Restrict Inbound Access:** Do not allow unrestricted access to port 9093 from the internet or untrusted networks.
* **Implement Firewalls:** Configure firewalls to permit connections to port 9093 only from authorized sources (e.g., internal networks, VPNs, specific IP addresses).
* **Authentication/Authorization:** Configure Prometheus (and Alertmanager) to require authentication if accessed over less trusted networks, even internally.
* **TLS Encryption:** Use TLS/SSL to encrypt communication with the Prometheus web UI/API if accessed over potentially insecure networks.
By securing port 9093, you help protect the sensitive monitoring data collected by Prometheus and prevent potential misuse of the system.
