root@orangerie:~# nc -l 8888 &
[1] 267
root@orangerie:~# ss -nltp | grep nc
LISTEN     0      1            *:44854                    *:*                   users:(("nc",pid=267,fd=3))
root@orangerie:~# nc localhost 44854
invalid connection to [127.0.0.1] from (UNKNOWN) [127.0.0.1] 51870
[1]+  Exit 1                  nc -l 8888