502 Bad Gateway in Web GUI at 1500+ Captive Portal Users – Need Tuning Suggestions

Networking & Firewalls
1

We are encountering a “502 Bad Gateway (nginx)” error in the Web GUI whenever the captive portal user count exceeds approximately 1,500. Under normal load conditions (below 1,000 users), the system operates without issues.

We seek your guidance on fine-tuning the configuration to support higher loads (2,000+ users).

Server Details:

  • Version: pfSense CE 2.7.2-RELEASE (amd64)

  • CPU: Intel® Xeon® Gold 5318Y @ 2.10GHz, 96 CPUs (2 packages × 24 cores × 2 threads), AES-NI enabled, QAT disabled

  • RAM: 128 GB

  • Storage: 1 TB HDD

2

I never use the captive portal so I don’t have much guidance to offer. I would check the logs for error messages when the issue occurs. If no on else here has any ideas you could post in their forums.