Socket doesn't work when using public ip on same machine - python

I made a program using Python that should connect to the server using a socket. I run the script on the same machine and when I tried with private ip it worked but public doesn't.
Client:
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(("46.126.xx.xxx",9454)) #I put the public ip of the server (same machine)
msg = s.recv(1024)
print(msg.decode("utf-8"))
Server
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(("0.0.0.0",9454))
s.listen(5)
while True:
clientsocket, address = s.accept()
print(f"Connection from {address} has been established!")
clientsocket.send(bytes("Welocme to the server", "utf-8"))
It does not give me any errors. I made lots of reasearch but couldn't figure out what the problem is.
Well I just put the public ip of the server in the client socket.connect() and expected it to connect but it didn't. I am running this on the same machine.

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Python socket ipv6 over network not working

I am trying to connect a server to a client in python with sockets.
The problem is that with ipv6 binding, it works on my local network. What I want is to connect it to another network. These programs are written in Python 3
Here is the code of server.py:
import socket
HOST = someip
PORT = someport
server = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
server.bind((HOST, PORT))
server.listen()
Source code of client.py:
import socket
HOST = someip
PORT = someport
client = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
client.connect((HOST, PORT))
I think it is a port forwarding problem.
I know the code does nothing right now, but I want to first establish the connection.
When the server receives a request, we need to put it in a loop to accept it.
Like this
import socket
HOST = someip
PORT = someport
server = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
server.bind((HOST, PORT))
server.listen()
while True:
try:
conn, addr = server.accept()
print(f"New request from {addr}")
except KeyboardInterrupt:
server.close()

Trying to make a server with sockets in python

I'm trying to make a chat app in Python and I'm having some trouble.
I made a server on which I can connect successfully by using the local IP address. However, when I try to connect to it on an another device with my public IP address, there seems to be a timeout, no errors occur and it's continuously trying to connect.
Edit: I've already set up port-forwarding for my IPv4 address. And the client is using the public IP.
server.py:
import socket
s = socket.socket()
host = socket.gethostbyname(socket.gethostname())
port = 2000
s.bind((host, port))
print("Server started, waiting for incoming connections")
s.listen(5)
connection, address = s.accept()
print("New connection from", address)
while True:
data = connection.recv(1024).decode()
print("received:", data)
ret = data + "+++++++"
connection.send(ret.encode())
client.py
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
host = #my public ip address from whatsmyip.com
port = 2000
s.connect((host, port))
print("Connected.")
while True:
message = input("msg: ")
s.send(message.encode())
data = s.recv(1024).decode()
print(data)
Well, first of all, is your server in a network with other devices? If you have a router there, the IP you see in whatsmyip.com is the router's, not your computer's, IP. So you'd be trying to connect to it.
You can check that with the command netstat.

Python3 TCP Server not seeing incoming messages from external device

I want to create a small TCP server that takes incoming TCP connections from a device that is hooked up via Ethernet to my computer.
The physical port for that has the IP 192.168.1.100 statically assigned to it.
The scripts I use as a client and server are listed at the bottom.
The setup works if I want to send messages between the python scripts. However, I am unable to receive anything from the external device (screenshot from Wireshark capture below). From what I have read I can define an interface to listen to by defining its IP. So I defined the IP of the interface as the host variable. However, I do not receive anything in my script but the messages sent by the other script. I had a similar situation already here on stackoverflow. I thought that defining the correct IP as the host would resolve this issue but it did not.
I am also having a hard time capturing the traffic between the two scripts with Wireshark at all. They did not show up anywhere.
I need to pick up these connections on the eth0 interface with the static IP 192.168.1.100:
tcp_server.py
import socket
# create a socket object
serverSocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# get local machine name
# host = socket.gethostname()
host = "192.168.1.100"
port = 9002
# bind to the port
serverSocket.bind((host, port))
# queue up to 5 requests
serverSocket.listen(5)
while True:
# establish a connection
clientSocket, addr = serverSocket.accept()
print("Got a connection from %s" % str(addr))
msg = 'Thank you for connecting' + "\r\n"
clientSocket.send(msg.encode('ascii'))
clientSocket.close()
and this as a client:
tcp_client.py
import socket
# create a socket object
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# get local machine name
# host = socket.gethostname()
host = "192.168.1.100"
port = 9002
# connection to hostname on the port.
s.connect((host, port))
# Receive no more than 1024 bytes
msg = s.recv(1024)
s.close()
print(msg.decode('ascii'))

communication between two computers via Python socket in a LAN failed

Two computers in a LAN connecting to a wireless router, one IP address is 192.168.1.106 (server), the other one is 192.168.1.107 (client), the gateway on both computer is 192.168.1.1 (the router itself).
The two computer can ping each in two directions which means there should be no problem with routing and the router itself. But I failed when I tried to use Python UDP socket, the server cannot get any information from the client, and same happened when I change the ip address. (But it works fine when server and client are on a same computer using local ip address, so the code is should be ok)
I am using the following code:
server:
import socket
address = ('192.168.1.106', 5678) # the server listening on address 192.168.1.106
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.bind(address)
while True:
data, addr = s.recvfrom(2048)
if data == "empty":
print "no data from client"
else:
print "received:", data, "from", addr
s.close()
client:
import socket
address = ('192.168.1.106', 5678) # the client send to address 192.168.1.106
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
while True:
msg = raw_input()
if not msg:
msg = "empty"
s.sendto(msg, address)
s.close()
Did you open the UDP port on the firewall on both comoutera?

Python- run socket script on the remote linux host

I have uploaded the server script to the public directory on the server machine. Then I try to connect to the server by a client, but I am not being connected. Here is my code snippets:
# Echo client program
import socket
HOST = 'www.dotpy.ir/server.py' # 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.send('Hello, world')
data = s.recv(1024)
s.close()
print 'Received', repr(data)
server:
# Echo server program
import socket
HOST = '' # 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.send(data)
conn.close()
These scripts seem to work well.
However, the script at the server must be run on the server for this to work. It's not enough for it to be uploaded to the public file area. What access do you have to the servers? Can you have scripts running on them?
If you succeed in running the script, then you will have to change the client script from:
HOST = 'www.dotpy.ir/server.py' # The remote host
to
HOST = 'www.dotpy.ir' # The remote host
The reason is that you will connect to the host itself. There the script will be running, listening to any inbound connections on the port specified. You can't conect to a specific script.
Good luck!

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