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LibreNMS

Interact with LibreNMS network monitoring system

Overview

The node integrates with the LibreNMS network monitoring system, specifically providing functionality to retrieve graphical data related to port groups. The "Get Graph" operation under the "Port Groups" resource fetches visual graph representations of specified port group types over a defined time range and with customizable dimensions.

This node is beneficial in scenarios where network administrators or engineers want to visualize traffic or performance metrics for specific categories of port groups (e.g., transit or peering) within their monitored network. For example, it can be used to generate bandwidth usage graphs for peering ports during a particular day or to monitor transit port activity over a custom time window.

Properties

Name Meaning
Group Types Comma-separated list of port group types to include in the graph (e.g., transit,peering).
Graph Options Collection of optional parameters to customize the graph output:
   From Start time for the graph data (e.g., timestamp or date string).
   To End time for the graph data (e.g., timestamp or date string).
   Width Width of the generated graph in pixels (default is 1075).
   Height Height of the generated graph in pixels (default is 300).

Output

  • The node outputs JSON data representing the graph information retrieved from LibreNMS for the specified port groups.
  • The exact structure of the JSON depends on the LibreNMS API response but typically includes graph metadata and possibly encoded image data or URLs referencing the generated graph.
  • If binary data is returned (such as an image), it would represent the visual graph of the port group metrics according to the requested parameters.

Dependencies

  • Requires connection to a LibreNMS instance with API access enabled.
  • An API authentication token or key credential must be configured in n8n to authorize requests.
  • The node uses the LibreNMS REST API v0 endpoint.
  • Network connectivity to the LibreNMS server is necessary.
  • Optional SSL certificate validation can be disabled if using self-signed certificates.

Troubleshooting

  • Invalid or missing API credentials: Ensure that the API key/token is correctly set up in the node credentials and has sufficient permissions.
  • Incorrect group types: Providing invalid or misspelled group types may result in empty or error responses. Verify the group type names against LibreNMS documentation.
  • Time range errors: The "From" and "To" parameters should be valid timestamps or date strings. Invalid formats might cause request failures.
  • Graph dimension issues: Extremely large or zero values for width/height could lead to rendering problems or API errors.
  • Network connectivity: Confirm that the n8n instance can reach the LibreNMS server URL and that firewall rules allow API communication.
  • SSL certificate errors: If using self-signed certificates, enable the option to skip SSL certificate validation in the node credentials.

Links and References

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