Issue: Users or services cannot connect to your server, application, or device from an external network (e.g., the internet or another subnet). Connection attempts time out or are actively rejected.
sudo firewall-cmd --list-all Check the services and ports sections. If your port is missing, inbound traffic is blocked. inbound traffic blocked, check firewall settings
Temporarily disable the firewall to confirm the issue (do not do this in production). Issue: Users or services cannot connect to your
sudo iptables -L -n -v Look for a default policy of DROP or REJECT on the INPUT chain. Example blocking line: inbound traffic blocked, check firewall settings
sudo ufw status verbose If inactive, enable it with sudo ufw enable . If active, check for rules like Deny from any or missing Allow rules for your port.
The firewall is blocking the incoming (inbound) traffic.