Question

I’m currently working on with Sockets using Python.

As a starter, I tried copying first the examples given in this (17.2.2. Example) tutorial

I put the client and the server scripts in two different machines (of course)

Now, I want to try if it works, but I’m kind of lost.

I’m thinking of running the server program continuously so that it will keep on receiving the data sent by the client program. However, when I tried to run the Server program, it is giving me this error

socket.error: (99, ‘Cannot assign requested address’)

and When I tried running the client program, it doesnt give me errors, however, it is printing random data, which is different from what I’m expecting because I sent the String “Hello World”, So im expecting that it will receive and print “Hello World”

Shown below is the server program

# Echo server program
import socket

HOST = '192.168.104.112'                 # Symbolic name meaning all available interfaces
PORT = 50007              # Arbitrary non-privileged port
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((HOST, PORT))
s.listen(1)
conn, addr = s.accept()
print 'Connected by', addr
while 1:
    data = conn.recv(1024)
    if not data: break
    conn.sendall(data)
conn.close()

and the one below is the client program

# Echo client program
import socket

HOST = '192.168.104.111'    # The remote host
PORT = 50007              # The same port as used by the server
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST, PORT))
s.sendall('Hello, world')
data = s.recv(1024)
s.close()
print 'Received', repr(data)

Assuming that the IP of the machine that runs the server program is : 192.168.104.111

while the Client program is : 192.168.104.112

Im not really sure where to get the port number so I just used the port showed in the rpyc in the terminal. how do I get the correct port number anyway?

I know I made a lot of mistakes here. I just don’t which part. Could you point me the mistakes that i’ve done and how to correct them? and how do I run these programs?

BTW, i’m using Centos.

Answer 1

On the server, HOST should be either 0.0.0.0 or the server’s own IP address. The server needs to bind its listening port to its own interface(s). The client connects to the server.

Your client program doesn’t check for errors. So if it can’t connect to the server, things go awry.