无法从本地计算机连接到AWS EC2(Ubuntu)上的TCP服务器

https://docs.python.org/3/library/socket.html#example

# Echo server program
import socket

HOST = ''                 # Symbolic name meaning all available interfaces
PORT = 50007              # Arbitrary non-privileged port
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
    s.bind((HOST, PORT))
    s.listen(1)
    conn, addr = s.accept()
    with conn:
        print('Connected by', addr)
        while True:
            data = conn.recv(1024)
            if not data: break
            conn.sendall(data)

# Echo client program
import socket

HOST = '1.2.3.4'         # The remote host (I change this with my box's IP)
PORT = 50007              # The same port as used by the server
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
    s.connect((HOST, PORT))
    s.sendall(b'Hello, world')
    data = s.recv(1024)
print('Received', repr(data))

注意:我使用的是实际的EC2 IP,而不是1.2.3.4

如果我在本地机器上运行客户机,而在远程机器上运行服务器(由vultr托管),它就可以工作。

但如果将服务器托管在AWS EC2实例上,则不会。

我进入了EC2实例的安全组,添加了入站+出站“自定义TCP+UDP”规则。我尝试过允许服务器使用的特定端口,以及 0-65535 .

我想不出还有什么好尝试的。