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How to connect client in a internet to the server

I made a simple chat room. But I can't connect clients who joined through internet. I know I'm using local network to this program. But I researched how to connect my server to the internet. I used my Dynamic public IP and port forwarded using my router, but It didn't work. And I used ngrok, but it also didn't work. How can I solve this problem.
This is a part of my program.
IP_Address = 'IP'
Address = (IP_Address,PORT)
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.bind(Address) # Bind IP address and Port to this socket.
When I used my public addressit shows this error.
Traceback (most recent call last):
File "Documents/Projects/Python/server.py", line 13, in <module>
server.bind(Address) # Bind IP address and Port to this socket.
OSError: [Errno 99] Cannot assign requested address

Use server.bind(('',port)) or server.bind(('0.0.0.0',port)). Both mean "bind to all interfaces".
If you want to bind to a specific interface, use your local IP, not the public one. Use ipconfig from the console to see your IP address.
On the router, forward the port to your local IP. Clients on the internet connect to your public IP and port.

I think the best way to solve this problem is using a Cloud Application Platform to run the server program.

python socket programming : error trying to connect to server

I'm a beginner in python socket programming and I have to send a message from the server to the client side . I have 2 python IDLES one for the server and one for the client. I have made the server file with no errors but when I create a connection socket in my client file and try to connect to server I get the error:
clientSocket.connect((servername,port))
ConnectionRefusedError: [WinError 10061] no connection could be made because the target machine actively refused it
I don't know how to deal with this error and I would appreciate your help with guiding me.
Thank you in advance.
My code:
Server:
from socket import *
port = 1234
serverSocket = socket(AF_INET,SOCK_STREAM)
serverSocket.bind(('',port))
serverSocket.listen()
print("Server has started")
data = "Network labs"
while True:
connectionSocket , addr = serverSocket.accept()
connectionSocket.send(data)
connectionSocket.close()
Client:
from socket import *
port = 1234
servername = 'localhost'
clientSocket = socket(AF_INET,SOCK_STREAM)
clientSocket.connect((servername,port)) #this is where the error happens

I would gradually try to understand where the problem is coming from.
Try to identify where the problem is:
Write an example which is available online and will surely works, and then you will know that the problem is in your code.
Try to use the same code on different computer, or a VM. If it will work there you will know that the problem is with the environment.
Try to find people with similar problems, you will usually won't be the first. - Errno 10061 : No connection could be made because the target machine actively refused it ( client - server ) - this seems nice.
Find out if your server is running correctly, checks if someone is listening on port 1234 before running the client. (Use netstat)
Few things which unrelated to the subject but will improve your coding:
1. Don't import *, it's just an easy way to get name collision.
2. Use conventions, it's just make everything nicer to read. https://www.python.org/dev/peps/pep-0008/
Of course you can ignore all of this, it's just an advice.

Python 2.7 [Errno 113] No route to host

I have 2 computers on the same LAN. The first PC has an ip address 192.168.178.30, the other PC has an ip address 192.168.178.26.
Ping, traceroute, telnet, ssh, everything works between the two PCs. Both PCs run the same OS - CentOS 7 and both PCs have the same python version 2.7.5 (checked with the python -V command).
I copied simple python code from a computer networking book.
client.py
from socket import *
serverName = '192.168.178.30'
serverPort = 12000
clientSocket = socket(AF_INET, SOCK_STREAM)
clientSocket.connect((serverName,serverPort))
sentence = raw_input('Input lowercase sentence: ')
clientSocket.send(sentence)
modifiedSentence = clientSocket.recv(1024)
print 'From Server:', modifiedSentence
clientSocket.close()
server.py
from socket import *
serverPort = 12000
serverSocket = socket(AF_INET,SOCK_STREAM)
serverSocket.bind(('192.168.178.30',serverPort))
serverSocket.listen(5)
print 'The server is ready to receive'
while 1:
connectionSocket, addr = serverSocket.accept()
sentence = connectionSocket.recv(1024)
capitalizedSentence = sentence.upper()
connectionSocket.send(capitalizedSentence)
connectionSocket.close()
The code works when it is ran on the same PC (where the server is listening on localhost).
When I run the client code on one PC and the server code on the other PC I get this error on the client side.
Traceback (most recent call last):
File "client.py", line 5, in <module>
clientSocket.connect((serverName,serverPort))
File "/usr/lib64/python2.7/socket.py", line 224, in meth
return getattr(self._sock,name)(*args)
socket.error: [Errno 113] No route to host
Can someone help?

Check the firewall (on the server).

I stopped the firewall like Messa suggested and now it works.
service firewalld stop
I still don't understand what the problem was. I even tried using different distributions. Do all distributions have strict firewalls or something. For example Ubuntu to Ubuntu, Ubuntu to CentOS, CentOS to Ubuntu I still had the same problem (error).

~]#supervisord
Error: No config file found at default paths (/usr/etc/supervisord.conf, /usr/supervisord.conf, supervisord.conf, etc/supervisord.conf, /etc/supervisord.conf); use the -c option to specify a config file at a different path
For help, use /usr/bin/supervisord -h
You should use
ln -s /etc/supervisor/supervisord.conf /usr/etc/supervisord.conf

None of this stuff worked for me. I just connected both the devices to the same WiFi network and my program worked!

You can also get this same error ([Errno 113] No route to host) if you are trying to connect 2 devices on the same network. the error can be fixed by double checking to make sure both devices are connected to the mqtt_client or whatever you are using. as soon as I connected the device I was trying to talk to everything worked as to be expected.I would also check to make sure the right IP_Address is being passed

We had this problem. I am putting our findings here in case anyone else stumbles across this question like I did.
Our configuration:
Host A: IP address 192.168.0.1, netmask 255.255.255.0
Host B: IP address 192.168.1.1, netmask 255.255.254.0
Neither host has a default gateway.
We are connecting from Host B to Host A. (That is not a typo.) The connect call succeeds, but when we try to send data, we get errno 113 aka. EHOSTUNREACH aka. "No route to host".
The fix, of course, was to change the subnet on Host A to match Host B.
We were surprised to see this error on a connection within the same subnet / same LAN. And we were surprised that connect succeeded followed by send failing. And we were surprised to see this error on Host B even though the network configuration on Host B itself was fine.
Somehow, the incorrect subnet on Host A caused this error on Host B...
...and just like that, today I learned about ICMP "destination unreachable" messages.

library socket: open port

I have try to create a little online game with python but I face a problem.
I have no problem as long as I work in local (same computer or private IP adresse) but the socket can't connect if i use an IP.
Server:
import socket
co_prin = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
co_prin.bind(('', 9000))
co_prin.listen(10)
co,info=co_prin.accept()
print('connexion recu')
co.close()
co_prin.close()
Client:
import socket
co_serv=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
adresse='81.56.76.61'
co_serv.connect((adresse, 9000))
print("Connecté.")
co_serv.close()
If I change adresse by 'localhost' there is no problem.
One tell me that the reason was python can't open the port. I would like to know if there is a solution to solve or bypass the problem easy to use for other user. (I can always create a local network with hamachi or open the port manually but it's wouldn't be easy to share my programm).
Edit, the error in the client code: Traceback (most recent call last):
File "", line 5, in
co_serv.connect((adresse, 9000))
socket.error: [Errno 10061] No connection could be made because the target machine actively refused it

You are not using your actual computer IP. You are using your public IP address.
Open cmd/command.com and type in the command: ipconfig.
You will there see a totally different IP (IPv4/IPv6 address):
Most likely you want this (do this for yourself!):
Then, if you want people outside your network want to access your computer you must port forward the port to your network IP address from your router.
If you are just experimenting with python, it's best to use 127.0.0.1 or localhost as IP-address.

How to very SIMPLY deploy a Twisted Server on OPenshift

I've got the right environment setup, python 2.7.5, Twisted installed and imports work in the Python Shell.
I have a very simple Server instance to display a landing page that Works on local machine fine.
from twisted.web import http
class MyRequestHandler(http.Request):
pages={
'/': '<h1>Geo-Address Server</h1>Twisted Server is Up and Running..',
'/test': '<h1>Test</h1>Test page',
}
def process(self):
print self.path
if self.pages.has_key(self.path):
self.write(self.pages[self.path])
else:
self.setResponseCode(http.NOT_FOUND)
self.write("<h1>Not Found</h1>Sorry, page does not exist")
self.finish()
class MyHttp(http.HTTPChannel):
requestFactory=MyRequestHandler
class MyHttpFactory(http.HTTPFactory):
protocol=MyHttp
if __name__=='__main__':
from twisted.internet import reactor
reactor.listenTCP(8080, MyHttpFactory())
reactor.run()
However, deploying this on the Openshift Server fails to run. If I try to run the script
python script.py &
I get:
reactor.listenTCP(8080, MyHttpFactory()) File
"/var/lib/openshift/5378ea844382ec89da000432/python/virtenv/lib/python2.7/site-packages/twisted/internet/posixbase.py",
line 495, in listenTCP
p.startListening() File "/var/lib/openshift/5378ea844382ec89da000432/python/virtenv/lib/python2.7/site-packages/twisted/internet/tcp.py",
line 979, in startListening
raise CannotListenError(self.interface, self.port, le) twisted.internet.error.CannotListenError: Couldn't listen on any:8080:
[Errno 13] Permission denied.
Reading through SO, most people just say to bind to port 8080(which I have done), but still I get the same error.

As the kb says
Please note: We don't allow arbitrary binding of ports on the
externally accessible IP address.
It is possible to bind to the internal IP with port range: 15000 -
35530. All other ports are reserved for specific processes to avoid conflicts. Since we're binding to the internal IP, you will need to
use port forwarding to access it:
https://openshift.redhat.com/community/blogs/getting-started-with-port-forwarding-on-openshift
Therefor, just find out the $OPENSHIFT_PYTHON_IP
echo $OPENSHIFT_PYTHON_IP
Then add that address to the reactor listener's interface
reactor.listenTCP(15000, MyHttpFactory(), interface='127.X.X.X')
Alternative(and the best) way to do it is by picking the value in the code. That way, if the IP changes dynamically, you still get the current IP
import os
local_hostname =os.getenv("OPENSHIFT_INTERNAL_IP")
..
..
reactor.listenTCP(15000, MyHttpFactory(), interface=local_hostname)
Note: You can only bind to the port range (15000-35530)