Problem

502 error

2021/12/14 22:52:13 [crit] 9524#0: *22859 connect() to 127.0.0.1:2368 failed (13: Permission denied) while connecting to upstream, client: 111.30.182.61, server: nocoder.org, request: "GET /dfs-maze/ HTTP/1.1", upstream: "http://127.0.0.1:2368/dfs-maze/", host: "nocoder.org"

Solution

Temporarily effective

setenforce 0

or permanently effective after reboot

vim /etc/selinux/config

SELINUX=disabled