In firewalld, you can define which ports to allow through using the following methods:
Allow a Specific Port
To allow a specific port (e.g., TCP port 8080), run:
sudo firewall-cmd --zone=public --add-port=8080/tcp --permanent
- --zone=public: Specifies the firewall zone (change as needed).
- --add-port=8080/tcp: Opens TCP port 8080.
- --permanent: Makes the rule persist after a reboot.
- Omit --permanent if you want it to be temporary.
Then reload the firewall to apply changes:
sudo firewall-cmd --reload
Allow a Range of Ports
For a range of ports (e.g., 5000-5100), use:
sudo firewall-cmd --zone=public --add-port=5000-5100/tcp --permanent sudo firewall-cmd --reload
Allow a Service Instead of a Port
If the service you need is predefined in firewalld, you can allow it by name instead:
sudo firewall-cmd --zone=public --add-service=http --permanent sudo firewall-cmd --reload
To list available services:
firewall-cmd --get-services
Check Open Ports
To verify which ports are open:
sudo firewall-cmd --list-ports