Error "proxy server is refusing connections" during Web Connections on RHEL8

Symptoms

Browser displays "proxy does not allow connections" or similar error message when connecting to web targets on RHEL8.

Solution

RHEL8 firewalld and docker-ce are not compatible with each other out of the box (additional info here). To address this, please run these commands on the carrier host as root:

# firewall-cmd --permanent --zone=trusted --add-interface=docker0
# service privx-carrier stop
# service docker stop
# service firewalld restart
# service docker start
# service privx-carrier start