NetWorker 8 Service and Connection ports

NetWorker 8 uses both service ports and connection ports, but whare are these ports and how are they utilised.

Service ports

Service ports are also known as listener ports or destination ports. The TCP server processes that run on each NetWorker host uses service ports to listen for inbound connections. NetWorker uses two types of service ports:

• Fixed ports — NetWorker uses two fixed ports: TCP/7937 and TCP/7938. You must include these ports in the service port range of each NetWorker host. NetWorker uses these ports to initiate connections.
• Variable ports — NetWorker dynamically opens ports. A NetWorker host can allocate any port in the defined service port range and the NetWorker daemons select the dynamic ports within that range randomly. The default range is 7937-9936. You can narrow or expand this range, as discussed in this chapter. To increase security in the environment, reduce this range to specify only the minimum number of service ports that the NetWorker software requires. The minimum value depends on the installation type and number of hosted NetWorker devices, if any. NetWorker stores the service port range in the NSR system port ranges resource in the NSR Local Agent (NSRLA) database of each NetWorker host.

Connection ports

Connection ports are also known as communication ports, source ports, or outbound ports. NetWorker processes use connection ports to connect to a service. The NetWorker software requires one connection port for any type of communication between the client, storage node, and server.

NetWorker uses a default range, 0-0 to indicate that the NetWorker software allows the operating system to select the port for TCP clients. The operating system reserves connection ports for short-term use and reuses them, as needed. The operating system might allow you to configure the dynamic port range, for example by using netsh on Windows. NetWorker does not require modifications to this range and EMC recommends that you use the default dynamic port range.