NGINX SSL reverse proxy error: recv() failed (104: Connection reset by peer)

[mahesh]

Question
NGINX SSL reverse proxy error: recv() failed (104: Connection reset by peer) while reading response header from upstream
Symptoms

• Multiple nginx errors similar to the following are found in

/var/www/vhosts/example.com/logs/proxy_error_log:

Code Select Expand

2022/11/28 15:08:12 [error] 2680#0: *636733 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 203.0.113.2, server: example.com, request: "POST /wp-comments-post.php HTTP/1.0", upstream: "http://203.0.113.1:7080/wp-comments-post.php", host: "example.com", referrer: "http://example.com/how-to-test/"
2022/11/28 15:42:35 [error] 2680#0: *649874 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 203.0.113.2, server: example.com, request: "POST /wp-comments-post.php HTTP/1.0", upstream: "http://203.0.113.1:7080/wp-comments-post.php", host: "example.com", referrer: "http://example.com/how-to-test/"
2022/11/28 15:45:50 [error] 2680#0: *651394 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 203.0.113.2, server: example.com, request: "POST /wp-comments-post.php HTTP/1.0", upstream: "http://203.0.113.1:7080/wp-comments-post.php", host: "example.com", referrer: "http://example.com/how-to-test/"
2022/11/28 16:58:16 [error] 2680#0: *683892 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 203.0.113.2, server: example.com, request: "POST /wp-comments-post.php HTTP/1.0", upstream: "http://203.0.113.1:7080/wp-comments-post.php", host: "example.com", referrer: "http://example.com/how-to-test/"
2022/11/28 15:08:12 [error] 2680#0: *636733 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 203.0.113.2, server: example.com, request: "POST /wp-comments-post.php HTTP/1.0", upstream: "http://203.0.113.1:7080/wp-comments-post.php", host: "example.com", referrer: "http://example.com/how-to-test/"
2022/11/28 15:42:35 [error] 2680#0: *649874 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 203.0.113.2, server: example.com, request: "POST /wp-comments-post.php HTTP/1.0", upstream: "http://203.0.113.1:7080/wp-comments-post.php", host: "example.com", referrer: "http://example.com/how-to-test/"
2022/11/28 15:45:50 [error] 2680#0: *651394 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 203.0.113.2, server: example.com, request: "POST /wp-comments-post.php HTTP/1.0", upstream: "http://203.0.113.1:7080/wp-comments-post.php", host: "example.com", referrer: "http://example.com/how-to-test/"
2022/11/28 16:58:16 [error] 2680#0: *683892 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: 203.0.113.2, server: example.com, request: "POST /wp-comments-post.php HTTP/1.0", upstream: "http://203.0.113.1:7080/wp-comments-post.php", host: "example.com", referrer: "http://example.com/how-to-test/"
[size=5]Cause
[/size]This error can appear due to the use of the Nginx reverse proxy web server without ensuring that you are passing your SSL when proxying all connections.
Resolution
1. Log into Plesk

2. Go to Domains > example.com > Hosting & DNS > Apache & nginx Settings

3. Add the following line in Additional nginx directives

proxy_ssl_server_name on;
4. Scroll down and press OK to apply the changes.