The tnsping utility is used to determine whether or not an Oracle service can be successfully reached.
If a connection can be established from a client to a server (or server to server), tnsping will report the number of milliseconds it took to reach the remote service. If unsuccessful, a network error will be displayed. However, tnsping will only report if the listener process is up and provides no indication of the state of the database.
C:\>tnsping <net service name> <count>
The <net service name> must exist in the tnsnames.ora file. This file is used by clients and database servers to identify server destinations. It stores the service names and database addresses. The <count> parameter is optional and will show the number of times the command should try to connect to the specified service name.