If you need to connect to specific servers instead of going through a proxy server, set the apiportal.proxy.noProxyHosts parameter to list those servers.

You can find this parameter in the apiportal.properties file. The file is located in the Software AG_directory \API-Portal\server\bin\work\work_apiportalbundle_m\base\webapps\abs\WEB-INF\classes\com\aris\modeling\server\webapp\apiportal\configuration directory.