On trying to start the Gateway engine getting the below error :
<<<
GatewayServer com.tibco.ax.gs.runtime.GatewayRuntimeException: Initializing webengine failed.
        at com.tibco.ax.gs.runtime.GatewayServer.initFCPService(GatewayServer.java:386)
        at com.tibco.ax.gs.runtime.GatewayServer.init(GatewayServer.java:115)
        at com.tibco.ax.gs.runtime.GatewayServer.<init>(GatewayServer.java:81)
        at com.tibco.ax.gs.runtime.GatewayServer.Startup(GatewayServer.java:618)
Caused by: java.io.IOException: Failed to activate application 'ddtp': Failed to start connector on port '12000': Connector failed to start: Protocol handler initialization failed: 0.0.0.0:12000/PORT_SECURE_CA
        at com.tibco.ax.fw.webengine.app.AppListener.activate(AppListener.java:43)
        at com.tibco.ax.fw.webengine.app.AppListener.activate(AppListener.java:30)
        at com.tibco.ax.gs.runtime.GatewayServer.initFCPService(GatewayServer.java:381)
        ... 3 more
>>>

The default settings were used for creating the token : Data port 12000 and Management port 11000

Unable to start Gateway engine on port 12000

Linux

Since 12000 is the default data port we use for BC gateway engine, please make sure it is not used by any other process. If already used, changing the port number to something else like 13000 should fix the issue. Also, the firewall needs to be open at this port between the interior and gateway server.

In addition to it, make sure the following property is commented out in the Admin TRA file (if exists) :
java.property.TIBCO_SECURITY_VENDOR=j2se.  If running the Administrator on a Windows machine as a service, make sure this value is deleted from the Windows registry:

Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\TIBCOAdmin-<your domain name>\Parameters\java.property.TIBCO_SECURITY_VENDOR

If these changes are made, make sure to restart the Admin as well as the Gateway engine.

NOTE : Usually when using a Linux environment, if you kill a process running at a particular port, make sure to wait for at least 2 minutes before checking back if any process is running at that port or not.
 

ddtp, gateway, 12000, PORT_SECURE_CA