# Configuration Firewall After successfully configuring the NAT Gateway, the next step is to configure the firewall on the Cloudeka portal service via the Security menu to add the IP address used by your computer. First check the IP address your computer uses in ifconfig.me in your browser.

On the Cloudeka portal service, select the Security menu and press the Create Security Group button to add the firewall configuration that will be used.

The Create Security page appears, fill in the Name, Description columns, and to add an entry rule, press the New Rule button.

Because the DNAT configuration on the NAT Gateway uses port 2255, in the Type column select Custom TCP Rule, in the Port Range (Min/Max) column enter port 2255, and in the Sources column enter the IP address obtained from ifconfig.me. Select the virtual machine to which the Firewall configuration will be applied and press the Create Security Firewall button.

--- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.cloudeka.id/deka_flexi/nat-gateway/remote-putty/configuration-firewall.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.