1. Problem

Recently encountered this issue when using nginx as a reverse proxy:

2024/02/19 17:15:32 [crit] 3025#3025: *2 connect() to 127.0.0.1:19010 failed (13: Permission denied) while connecting to upstream, client: 10.64.68.30, server: , request: "POST /opticTransceiver/addDeviceList HTTP/1.1", upstream: "http://127.0.0.1:19010/opticTransceiver/addDeviceList", host: "localhost:8080", referrer: "http://localhost:8080/device-connect"

2. Cause

This is due to SELinux restrictions.

3. Solutions

1. Disable SELinux Restrictions

1) Temporarily Disable (No need to restart machine)

setenforce 0 ##Set SELinux to permissive mode

2) Modify Configuration File (Requires machine restart)

Edit the /etc/selinux/config file

Change SELINUX=enforcing to SELINUX=disabled

Restart the machine

2. Execute the Following Command

setsebool -P httpd_can_network_connect 1