CODEWITHSUNDEEP
pythonudp
cancub
cancub

Reputation: 23

An existing connection was forcibly closed by the remote host (simple UDP client-server)

Absolute newbie here, and I can't quite seem to find the answer to my question. Running python 2.7.

My code for the server is as follows:

#UDPPingerClient.py
from socket import *

#Create a UDP socket
clientSocket = socket(AF_INET, SOCK_DGRAM)
#Assign IP address and port number to socket
clientSocket.bind(("127.0.0.1",9501))

#Set a timeout value of 1 second
clientSocket.settimeout(1)

msg = "test"

#the server info
sIP = "127.0.0.1"
sPort = 12007
addr = (sIP,sPort)

a = 10

# the server will automatically drop some messages
# so we send 10 to make sure it gets there and then
# listen for a response from the server
while a > 0:
    clientSocket.sendto(msg,addr)
    try:
        received, server = clientSocket.recvfrom(1024)
        print received
    except timeout:
        print ('an error occured')

    a = a - 1

The server code:

# UDPPingerServer.py 
# We will need the following module to generate randomized lost packets 
import random 
from socket import * 

# Create a UDP socket 
# Notice the use of SOCK_DGRAM for UDP packets 
serverSocket = socket(AF_INET, SOCK_DGRAM) 
# Assign IP address and port number to socket 
serverSocket.bind(("127.0.0.1", 12007)) 

while True: 
    # Generate random number in the range of 0 to 10 
    rand = random.randint(0, 10) 
    # Receive the client packet along with the address it is coming from 
    message, address = serverSocket.recvfrom(1024) 
    # Capitalize the message from the client 
    message = message.upper()
    12 # If rand is less is than 4, we consider the packet lost and do not respond
    if rand < 4:
        continue 
    # Otherwise, the server responds 
    serverSocket.sendto(message, address)

Thus far I haven't been able to get a reply from the server. The most I've been able to accomplish is sending once and timing out before getting this error:

an error occured <-- output from exception

Traceback (most recent call last):
  File "C:/Python27/UDPPingerClient.py", line 23, in <module>
    received, server = clientSocket.recvfrom(1024)
error: [Errno 10054] An existing connection was forcibly closed by the remote host

The reproducibility on this one is 100%, this is the outcome every time I run the server file and then the client file. Same thing with the firewall on or off. I have a feeling this has to do with the exception but I can't quite wrap my head around why.

Upvotes: 0

Views: 4345

Answers (1)

FoggyDew
FoggyDew

Reputation: 211

this is the output i got:

foggy@dew ~ $ python UDPPingerClient.py 
TEST
TEST
an error occured
TEST
TEST
TEST
an error occured
TEST
an error occured
TEST

exactly ten messages, some have timeouted others were passed back. besides that extra 12 above rand line in Server (and that doesn't bother the interpreter) i don't see anything wrong with the code.

Upvotes: 0

Related Questions