# Network rules

To further lock down the communication in between the nodes in your SonarQube Server cluster, you can define the network rules. The setup depends on the installation type.

<table><thead><tr><th width="95">Protocol</th><th width="134">Source</th><th width="132">Destination</th><th width="288">Port</th><th>Default</th></tr></thead><tbody><tr><td>TCP</td><td>Reverse Proxy</td><td>App Node</td><td><code>sonar.web.port</code></td><td>9000</td></tr><tr><td>TCP</td><td>App Node</td><td>Search Node</td><td><code>sonar.cluster.node.search.port</code></td><td>9001</td></tr><tr><td>TCP</td><td>Search Node</td><td>Search Node</td><td><code>sonar.cluster.node.es.port</code></td><td>9002</td></tr><tr><td>TCP</td><td>App Node</td><td>App Node</td><td><code>sonar.cluster.node.port</code></td><td>9003</td></tr></tbody></table>

You can further segment your network configuration if you specify a frontend, a backend and a search network:

<table><thead><tr><th width="112">Network</th><th>Parameter</th><th>Description</th></tr></thead><tbody><tr><td>Frontend</td><td><code>sonar.web.host</code></td><td>Frontend HTTP Network</td></tr><tr><td>Backend</td><td><code>sonar.cluster.node.host</code></td><td>Backend App to App Network</td></tr><tr><td>Backend</td><td><code>sonar.cluster.search.hosts</code></td><td>Backend App to Search Network</td></tr><tr><td>Search</td><td><code>sonar.cluster.node.search.host</code></td><td>Backend Search to Search Network</td></tr></tbody></table>

For information about the parameters, see [dce-specific](https://docs.sonarsource.com/sonarqube-server/server-installation/system-properties/dce-specific "mention").

## Related pages <a href="#related-pages" id="related-pages"></a>

* [securing-behind-proxy](https://docs.sonarsource.com/sonarqube-server/server-installation/data-center-edition/network-security/securing-behind-proxy "mention")
* [elasticsearch-security-features](https://docs.sonarsource.com/sonarqube-server/server-installation/data-center-edition/network-security/elasticsearch-security-features "mention")