Resolving Reverse Proxy Host Header Issues
I was having an issue with my website. When I used my browser to navigate to https://alain.apigban.com, there was nothing displayed.
The setup is like this:
User > Frontend proxy (Caddy) > Backend HTTP Server (Caddy)
The frontend proxy receives the request, and here’s one line from the frontend proxy access logs:
{"level":"debug", "ts":1740849407.8355885,"logger": "http.handlers.reverse_proxy", "msg":"upstream roundtrip", "upstream": "backend_server_1_IP:10000", "duration": 0.01451143, "request": {"remote_ip": "client_IP", "remote_port": "56466","client_ip": "client_IP", "proto": "HTTP/2.0", "method": "GET", "host": "alain.apigban.com", "uri":"/posts/ansible/02/netbox-source-of-truth/", "headers": {"Priority":["u=0, i"], "Sec-Fetch-Mode": ["navigate"], "X-Forwarded-For":["client_IP"], "Sec-Fetch-User": ["?1"], "Accept-Encoding": ["gzip, deflate, br, zstd"], "Upgrade-Insecure-Requests": ["1"], "Sec-Fetch-Dest": ["document"], "X-Forwarded-Host": ["alain.apigban.com"], "User-Agent": ["Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:135.0) Gecko/20100101 Firefox/135.0"], "Accept-Language": ["en-US,en;$q=0.5"], "Sec-Fetch-Site": ["none"], "X-Forwarded-Proto": ["https"], "Te": ["trailers"], "Accept": ["text/html,application/xhtml+xml,application/xml;$q=0.9,*/*;$q=0.8"]},"tls": {"resumed": false, "version": 772, "cipher_suite": 4865, "proto": "h2", "server_name": "alain.apigban.com"}},"headers": {"Date": ["Sat, 01 Mar 2025 17:16:47 GMT"], "Content-Length":["0"], "Server": ["Caddy"]},"status":200}
