= [Network] Check Ports in Use
== [Unix-like]
=== [ss]
[[[#!Vim sh
sudo ss -tulpn
]]]
[[[
Netid                  State                   Recv-Q                   Send-Q                                     Local Address:Port                                      Peer Address:Port                  Process
udp                    UNCONN                  0                        0                                          127.0.0.53%lo:53                                             0.0.0.0:*                      users:(("systemd-resolve",pid=638,fd=13))
udp                    UNCONN                  0                        0                                                0.0.0.0:68                                             0.0.0.0:*                      users:(("dhclient",pid=519,fd=9))
udp                    UNCONN                  0                        0                                                0.0.0.0:17500                                          0.0.0.0:*                      users:(("dropbox",pid=366138,fd=54))
tcp                    LISTEN                  0                        511                                              0.0.0.0:443                                            0.0.0.0:*                      users:(("nginx",pid=2806651,fd=7),("nginx",pid=2806650,fd=7),("nginx",pid=2068522,fd=7))
tcp                    LISTEN                  0                        151                                              0.0.0.0:3306                                           0.0.0.0:*                      users:(("mysqld",pid=519580,fd=29))
tcp                    LISTEN                  0                        511                                              0.0.0.0:80                                             0.0.0.0:*                      users:(("nginx",pid=2806651,fd=6),("nginx",pid=2806650,fd=6),("nginx",pid=2068522,fd=6))
tcp                    LISTEN                  0                        128                                              0.0.0.0:17500                                          0.0.0.0:*                      users:(("dropbox",pid=366138,fd=53))
tcp                    LISTEN                  0                        128                                              0.0.0.0:22                                             0.0.0.0:*                      users:(("sshd",pid=1149111,fd=3))
tcp                    LISTEN                  0                        511                                            127.0.0.1:6379                                           0.0.0.0:*                      users:(("redis-server",pid=2583586,fd=18))
.
.
.
]]]

=== [lsof]
[[[#!Vim sh
sudo lsof -i -P
]]]
[[[
COMMAND       PID            USER   FD   TYPE    DEVICE SIZE/OFF NODE NAME
dhclient      519            root    9u  IPv4      2996      0t0  UDP *:68
systemd-r     638 systemd-resolve   13u  IPv4      3060      0t0  UDP localhost:53
systemd-r     638 systemd-resolve   14u  IPv4      3061      0t0  TCP localhost:53 (LISTEN)
java        18514          ubuntu  451u  IPv4 109868774      0t0  TCP localhost:42264->localhost:3306 (ESTABLISHED)
java        18514          ubuntu  459u  IPv4 109869086      0t0  TCP localhost:52510->localhost:3306 (ESTABLISHED)
java        18514          ubuntu  461u  IPv4 109869098      0t0  TCP localhost:60694->localhost:3306 (ESTABLISHED)
.
.
.
]]]

[[[#!Vim sh
sudo lsof -P -i :443
]]]
[[[
COMMAND     PID     USER   FD   TYPE    DEVICE SIZE/OFF NODE NAME
dropbox  366138   ubuntu   28u  IPv4 109869434      0t0  TCP ip-172-31-18-21.ap-northeast-2.compute.internal:39146->162.125.40.2:443 (ESTABLISHED)
dropbox  366138   ubuntu   75u  IPv4 109869392      0t0  TCP ip-172-31-18-21.ap-northeast-2.compute.internal:45662->162.125.40.1:443 (ESTABLISHED)
nginx   2068522     root    7u  IPv4  55160814      0t0  TCP *:443 (LISTEN)
nginx   2806650 www-data    4u  IPv4 109895746      0t0  TCP ip-172-31-18-21.ap-northeast-2.compute.internal:443->196.251.69.133:62339 (ESTABLISHED)
nginx   2806650 www-data    5u  IPv4 109888542      0t0  TCP ip-172-31-18-21.ap-northeast-2.compute.internal:443->nbl216.ntup.net:52673 (ESTABLISHED)
nginx   2806650 www-data    7u  IPv4  55160814      0t0  TCP *:443 (LISTEN)
nginx   2806650 www-data   15u  IPv4 109895761      0t0  TCP ip-172-31-18-21.ap-northeast-2.compute.internal:443->221.147.112.178:62841 (ESTABLISHED)
nginx   2806650 www-data   16u  IPv4 109894716      0t0  TCP ip-172-31-18-21.ap-northeast-2.compute.internal:443->crawl-66-249-66-71.googlebot.com:53280 (ESTABLISHED)
nginx   2806651 www-data    7u  IPv4  55160814      0t0  TCP *:443 (LISTEN)
.
.
.
]]]