Firewall issues with database ports

If you experience database connection issues, you might need to ensure that the local firewall on each node is allowing requests to reach the node IP address and also check other firewall settings.

IBM Cloud Pak for Data System If you are using the IBM Cloud Pak for Data System hardware and software deployment, do not follow the recommendations in this topic. Follow the steps that are specific to the Cloud Pak for Data System.

Your cluster administrator must ensure that external IPs are routed to the nodes and local firewall rules on all nodes allow access to the open port. For more details, see Configuring ingress cluster traffic using a NodePort in the Red Hat® OpenShift® documentation:

Other firewalls settings to check:

Operating system

The Linux® command sudo iptables -F unlocks the port that was opened for the database connection.

firewalld management tool

If your Linux implementation is using the firewalld tool, the following commands are useful to ensure that ports are open for connection:

If firewalld is set to mask, the port will remain open.
If firewalld is set to enable, the tool might restore rules that can drop connections. In this situation, you can use the following commands to keep the port open:
```
firewall-cmd --permanent --add-port=X/tcp
firewall-cmd --reload
```