Here is the situation i met:
- Server is managed by laravel forge
- It is serving behind cloudflare reverse proxy
- Nginx is up and running, listening on both port 80 and 443 (confirmed)
now i need to configure a custom load balancer for this server, and there is a very weird thing happens, when I trying to curl the url from outside, the request is success, access log appended into nginx log, but when i trying to access it from the load balancer machine via curl --resolve, the connection closed before anything happens (no header no status, basically no response at all).
First, I thought it was a firewall configuration issue, so I ssh into the application server, and try curl --resolve xxxx:80:127.0.0.1 which is access it via loopback connection, but same thing happens.
Then I tried to do the same thing again with https, but the connection closed when client trying to initiate the TLS handshake.
The whole thing seems like the loopback being blocked which sounds impossible to me, so does anyone got any clue of how this issue happens?
p/s: I did check about the firewall, ufw is enabled but I am getting same result after ufw is disabled
In this picture, I should get 404 instead of no results at all
forge@dev-server1:~$ curl -v localhost
* Trying 127.0.0.1:80...
* TCP_NODELAY set
* Connected to localhost (127.0.0.1) port 80 (#0)
> GET / HTTP/1.1
> Host: localhost
> User-Agent: curl/7.68.0
> Accept: */*
>
* Empty reply from server
* Connection #0 to host localhost left intact
curl: (52) Empty reply from server
forge@dev-server1:~$
Update
Suggested by comment, I run nginx -T and then here is the output
p/s: here is the test for https i mentioned before
forge@dev-server1:~$ curl --resolve member.domain.hide:443:127.0.0.1 https://member.domain.hide -v
* Added member.domain.hide:443:127.0.0.1 to DNS cache
* Hostname member.domain.hide was found in DNS cache
* Trying 127.0.0.1:443...
* TCP_NODELAY set
* Connected to member.domain.hide (127.0.0.1) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
* CAfile: /etc/ssl/certs/ca-certificates.crt
CApath: /etc/ssl/certs
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* OpenSSL SSL_connect: Connection reset by peer in connection to member.domain.hide:443
* Closing connection 0
curl: (35) OpenSSL SSL_connect: Connection reset by peer in connection to member.domain.hide:443
forge@dev-server1:~$
