How to test the number of open sockets on the server?

Question

Computer networks

How can you generate a certain number of connections to different sockets from inside a certain server (windows or linux)?

Answer 1

It is necessary to check the setting on the router (virtual) that cuts the number of open socket connections.
set an easily verifiable limit, for example 2, and check with nmap that two nmaps start and establish a connection, but the connection fails in the third.
two different connections on the same port also requires two different sockets.