I am experiencing a persistent issue with the OPNSense WebGUI. After some unpredictable period of time, I am unable to access the OPNSense login page through the WebGUI. To resolve this, I have to log in via the console, select option 2, change HTTPS to HTTP, and reset the WebGUI. After these steps, I can access the login page again without problems. However, if I remain inactive for a long time, the WebGUI becomes unreachable once more, requiring me to repeat the same console steps.
The system log continuously shows this error whenever I cannot log in (one log entry per access attempt):
(/usr/obj/usr/ports/www/lighttpd/work/lighttpd-1.4.82/src/mod_openssl.c.4647) SSL: addr:192.168.10.17 ssl_err:1 error:0A00009C:SSL routines::http request
After performing the reset steps in the console, the log shows:
(/usr/obj/usr/ports/www/lighttpd/work/lighttpd-1.4.82/src/server.c.1271) [note] graceful shutdown started
(/usr/obj/usr/ports/www/lighttpd/work/lighttpd-1.4.82/src/server.c.2372) server stopped by UID = 0 PID = 93511
(/usr/obj/usr/ports/www/lighttpd/work/lighttpd-1.4.82/src/server.c.1971) server started (lighttpd/1.4.82)
(/usr/obj/usr/ports/www/lighttpd/work/lighttpd-1.4.82/src/h1.c.441) unexpected TLS ClientHello on clear port (192.168.10.17)
I am completely puzzled by this issue, and this problem does not occur on my other OPNSense systems. Could this be somehow related to HTTPS or HSTS?