Monitor my FortiGate firewall using Prometheus, SNMP Exporter, and Grafana

Hello Grafana team,
I need your help please.

I want to monitor my FortiGate firewall using Prometheus, SNMP Exporter, and Grafana.

SNMP on the FortiGate: working

SNMP Exporter: installed on the same server as Prometheus

In fortigate.yml, under the auth / community section, I configured the same community string (snmp) as on the firewall.

In prometheus.yml, I added the following configuration:

  • job_name: ‘fortigate-snmp’
    static_configs:
    • targets:
      • <FIREWALL_IP>
        metrics_path: /snmp
        params:
        module: [fortigate]
        relabel_configs:
    • source_labels: [address]
      target_label: __param_target
    • source_labels: [__param_target]
      target_label: instance
    • target_label: address
      replacement: localhost:9116

Under Prometheus, I am getting the following error:(Error scraping target: server returned HTTP status 400 Bad Request

Could you please help me identify what might be missing or misconfigured?

Thank you in advance for your support.