HAProxy: authentication in backend server (frappe/ERPNext) fails

[DomCa]

Hi all,

I am using OPNSense Firewall with HAProxy as reverse proxy. I have two servers running in the backend with SSL offloading. A jitsi server runs fine.

The frappe/erpnext server shows the start page, but after logging in, the login terminates with an error.
Access from my LAN network works fine.

I know that this may be a frappe/erpnext specific error. But I hope that there may be a header or option in HAProxy that may solve this issue.

Thanks
 DomCa