Discourse behind reverse proxy and https

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18

I migrated our discourse to a new setup and now have problems with http 403 on POST session during the login. I would guess a CSRF problem, but right now I have no idea where to start the debugging and /var/log/discourse-var-log/production.log and production_error.log all have 0 bytes …

Any ideas how to debug this properly?

The current setup:
1. haproxy as central https load balancer/accelerator (for both discourse and other services)

forum >> develd apache rev. proxy p.82
backend forum-backend
   mode http
   server forum.netzwissen.de 10.10.10.14:83 cookie A check
   http-request set-header X-Forwarded-Port %[dst_port]
   http-request add-header X-Forwarded-Proto https if { ssl_fc }
   # HSTS header, 16000000 seconds: a bit more than 6 months
   http-response set-header Strict-Transport-Security "max-age=16000000; includeSubDomains; preload;"

2. local apache as rev proxy

   <IfModule proxy_module>
    ## <https://meta.discourse.org/t/running-other-websites-on-the-same-machine-as-discourse/17247>
    ProxyPreserveHost On
    # ProxyRequests Off     
    RequestHeader set X-Forwarded-Proto expr=%{REQUEST_SCHEME}
    RequestHeader set X-Real-IP expr=%{REMOTE_ADDR}
    ProxyPass /  unix:/var/discourse/shared/web-only/apache.http.sock|http://localhost/
    ProxyPassReverse  / unix:/var/discourse/shared/web-only/apache.http.sock|http://localhost/
    </IfModule>

3) Discourse operating with separate web_only and data containers, web_only deployed with - “templates/web.socketed.template.yml”