JNLP port is missing from Configure Global Security in Jenkins
The 'TCP port for JNLP agents' setting seems to be not available anymore in the 'Configure Global Security' settings. Instead of that modify your agent's settings and set Launch method as 'Launch agent by connecting it to master'. It works similarly to the option that you are looking for:
Agents communicate through each other over TCP.In my case i couldnt find "TCP port for JNLP agents".Solution for it is,before creating an agent ,go to Configure global security ->section labeled "Agents" and the line that says "TCP port for inbound agents". Insert a valid port value for the TCP port for inbound agents. Apply that change.
Then goto Configure Jenkins -> Manage Nodes -> create new node or configure node Choose the setting "Launch agent by connecting it to the master" under Launch Method.
The phrasing has been improved significantly in the user interface by removing the references to "JNLP". The key difference between the agent protocols is not the underlying transport, but rather which end initiates the connection. The agent launch method that was formerly called "JNLP" is a launch method that initiates the agent connection from the agent to the master. The launch method called "ssh" initiates the connection from the master to the agent.