Oracle Linux 8: Fail to Open Port in FirewallD

Applies to:

Oracle Cloud Infrastructure - Version N/A and later

Linux OS - Version Oracle Linux 8.0 and later

Information in this document applies to any platform.

Symptoms

Open a new port or add a service in firewalld fail without error.

In the server, port 80 is opened:

$ firewall-cmd --list-all
public (active)
 target: default
 icmp-block-inversion: no
 interfaces: ens3
 sources: 
 services: cockpit dhcpv6-client ssh
 ports: 80/tcp
 protocols: 
 masquerade: no
 forward-ports: 
 source-ports: 
 icmp-blocks: 
 rich rules:

Trying to connect from another host:

$ nc -v <SERVER_IP_ADDRESS> 80
Ncat: Version 7.50 ( https://nmap.org/ncat )
Ncat: No route to host.

Changes

Open a new port or add a service in firewalld