$ wget -O- http://localhost:3000

...<p>Welcome to Express</p>...

$ sudo netstat -ntlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 127.0.0.1:27017         0.0.0.0:*               LISTEN      9167/mongod
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      1607/sshd
tcp        0      0 0.0.0.0:3000            0.0.0.0:*               LISTEN      13685/node
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN      1104/master
tcp6       0      0 :::22                   :::*                    LISTEN      1607/sshd
tcp6       0      0 ::1:25                  :::*                    LISTEN      1104/master

$ sudo iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

$ sestatus
SELinux status:                 disabled