We use Net Manager for server-side monitoring configuration:
1. Add the name of the listener (the name can be arbitrarily specified):
2. Add the listening address and port, the address is the ip of the server, and the port is 1521.
3. Add database service:
File---Save network settings!
After the configuration, the test found that the client could not connect to the server database remotely, indicating that there is no listener.
It should be the reputation of the listener program, restart the server to solve it. There are also other commands to directly start the monitoring, and you can also test it. I have not tested here, the server that is started directly.