A week back I posted this, and about 2 weeks back I posted this, both pertaining to an ever evolving issue with my Python sockets. I've also asked a question on the Wireshark Stack Exchange, and even after all 3 posts, I haven't been able to reach any conclusion. So heres the problem:
When I start up IDLE, it returns an error: IDLE Subprocess: socket error: No connection could be made because the target machine actively refused it and then I press ok on the dialogue boxes and it closes it out. But the issue isn't only limited to IDLE.
Any TCP ports I try to connect to via the Python socket module will fail. For example, if I run a server and a client (server first, of course, and both have the current IP of my computer and the port 45002) locally on my computer it returns: [Errno 10061] No connection could be made because the target machine actively refused it. So someone on an earlier post told me that running both the programs locally on a Windows machine will not work because it doesn't have a loopback interface (although when I look at my network interfaces via CMD, Loopback interface is listed for some reason). So then I went ahead and put the server on the computer with the issue, and the client on another computer on the network. It returns: [Errno 10060] A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond. But for some reason, if I run the server on the other computer and then run the client on the computer with the issue, the server and client actually connect, and then the server fails claiming: [Errno 10057] A request to send or receive data was disallowed because the socket is not connected and (when sending on a datagram socket using a sendto call) no address was supplied, even though I made sure to include a .connect(addr) in the client program. Sorry if this is getting confusing, but it's going to get a bit more complicated than this.
After this mess of running servers/clients on different computers, per request of another answerer on an early post, I installed Wireshark and began looking for packets being sent on the ports I am using. The results were a little weird. When I run the server on the computer with the issue, and the client on the other computer, Wireshark catches absolutely no packets on the port of the server, and the client fails with the errno 10060, as I said earlier. If I run the server from the other computer and the client from the computer with the issue, Wireshark catches some ordinary SYNs and ACKs. I only get an RST when I end the Python.exe process (this info is really only important to people who are good with Wireshark/networking, it's really only extra info).
I've also tried capturing packets from the IDLE program with Wireshark after I pinpointed the range of ports that it tends to use. When I start it up, no packets on any port in the range. Again, this is really just extra info to any of you who may be able to make something of it.
Again, sorry for the confusion, but I must go on.
And now, the issue that brought all this up. The problem that really caused me to ask myself "Hmm... Why is Python not working correctly?", my Twisted server was not able to import the reactor module returning the errno 10061. If you don't use/know of Twisted, all that's really needed to understand the problem is that, to import the reactor module, Twisted has to setup a Python TCP port, which is not working.
This issue has left me (and presumably everyone who's read it) scratching their head. I am sure that the ports I am using are not used. I'm sure the IP addresses are correct and matching. I am sure that there is no firewall blocking the connections, since I have tried running the programs without a firewall on with no luck. I am running a Wireless Windows 64bit laptop.
Heres my client program, and here's my server program, if they help at all.
Any suggestions, ideas, or answers are welcomed. At this point, any at all. Thanks.
P.S. If there is any info I can provide, or anything I can do to help find the solution to this issue, please tell. Also, I know this question is barely a programming one, so if there is somewhere else I am supposed to put this, please say and I'll move it over.
EDIT: Seems like I solved one piece of the puzzle. I can now connect a client on the computer with the issue to the computer with no issue, but not the other way around (running the client on the good computer, and running server on the broken one). I had to switch servSock.recv(buff) to cliSock.recv(buff) on the server side.
Related
I am trying to monitor network traffic coming in and out of my VM**. My VM is connected to a socket via TCP (IP, PORT) with the python socket library. Once connected, I am sending a stream of bytes to the socket and then close the connection. The VM runs Ubuntu 18.04 LTS. The connection is made in a VPN tunnel.
How do I capture the traffic for the source and destination while my python script runs? I have tried to work with scapy and Wireshark/pyshark, but the documentation I found did not help me a lot.
Does anyone have an idea how I could do this? I am using python 3
I use wireshark to capture packets, you can filter out the destination and source (as flags to), here's the docs. Is the VPN using some kind of security to encrypt information (such as TLS)?
In the filter insert:
ip.src==your.local.ip.addr && ip.dst==your.VM.ip.addr && ip.proto=="TCP"
What could happen is that the VM tries to get updates and wireshark can pickup a lot of packets, it can mess up your search for the information in the sockets (byte stream).
You also can try stop some Ubuntu services to prevent the internet use, but I cant tell you how to disable all.
Do you want to pickup that byte stream with a sniffer and convert into a person's eye?
If that's the case, it is advanced stuff I can't explain.
Hope I could help.
I wonder and i've been trying everything to get my program with python sockets to work remotely. When I say remotely is like, I run the server in my computer and my friend at his house can run the client and connect to my server. Is this possible without using Hamachi? Pls let me know, because I'm already dying by trying so many things and installing and uninstalling programs.
You have to activate port forwarding on your router so that everything that comes on the specific port is forwarded to your local IP (and the port should be open).
I'm working a tutorial in Python 3.8 that involves sockets and networking. There is a server.py file and a client.py file. I took example code straight out of the Python doc for sockets to see if that would work, and it does not. The server starts and creates a socket and listens for the connection, but I get WinError 10061, the one where the target machine refuses the connection. My OS is Windows 10 and I'm using IDLE. I've looked at my Firewall and set a permission for pythonw.exe to be allowed through, but that has not helped. Anybody have any fixes for me to try? I can't really proceed until I can get the client and server connected.
I think I know what I’ve been doing wrong. I have been running both server and client files in the same console. I think I have to open two consoles and run one file in each so they can communicate.
(Doh!)
I’m at work so I can’t test it right now. Just in case anyone else has been befuddled by this .
Yes, I did not realize that each file had to run in its own instance of IDLE, but that makes perfect sense now. A socket won’t connect to itself!
It seems the socket connection through paramiko (v1.10.0) is not stable.
I have two computers. The python code is on the PC one. The connection sometime is successful and sometime is not (Same code). When the PC paramiko code fails (socket.error, 10060), I use my Mac via terminal ssh login the server and everything is fine.
I use set_missing_host_key_policy in the code. But the Mac has the key I guess. I typed yes when login at the first time.
If the unstable connection is caused by the hotkey, how do I get the host key? From the server or somewhere in my local folder (win7)?
Try switching off Windows firewall. It's a network error, it should not be because of SSH key problems.
Error Code 10060: Connection timeout
Background: The gateway could not receive a timely response from the website you are trying to access. This might indicate that the network is congested, or that the website is experiencing technical difficulties.
Overview:
I have a device sitting on a local network to a computer that is sitting on an outside network. I would like to create a software program that allows me to seamlessly connect to the device from a computer on a different network. For purposes of this question, I've created a picture to help describe the network flow. What I need help with is what python packages I would need to develop the solution for this problem.
Details:
I have a computer MYPC (IP address 192.168.0.168) that is attached to the internet running through a proxy server (ROUTER1). I have full control over MYPC's environment, which is running Linux.
I have a second computer SOMESERVER (IP address 192.168.1.168) that is attached to the internet running through a proxy server (ROUTER2). In addition, SOMESERVER (IP address 10.0.0.159) is also attached to a local network (LOCAL). SOMESERVER is running windows. I have very limited control with SOMESERVER: I am able to send an executable to SOMESERVER that can run once before it is removed. I do not know the internet/world IP address of the ROUTER2 initially.
I have a device (DEVICE1) attached to SOMESERVER through LOCAL (IP address: 10.0.0.157).
I have another device (DEVICE2) attached to SOMESERVER through LOCAL (IP address: 10.0.0.158). DEVICE(x) runs linux. I have python on DEVICE(x) and I could install a pure python package if I needed to. However, I do not have the ability to compile for DEVICE(x).
I can connect between SOMESERVER and MYPC through the internet using SSH over ROUTER1 and ROUTER2. I can connect between SOMESERVER and DEVICE1 through the local network (LOCAL) using Telnet. I can connect between SOMESERVER and DEVICE2 through the local network (LOCAL) using Telnet.
I want to send a program to SOMESERVER that allows me seamless access over SSH and Telnet to DEVICE1 and DEVICE2 from MYPC. In addition, I want that program to be running python.
Here's a picture that helps explain the above problem:
Solution:
What I think I want is as follows. I need help with the details and what packages I might need to make it happen.
Part 1: The Dial Home Client and Server
Create a "dial home" server program (DIAL_HOME_SERVER) for MYPC which listens for any one dialing home and then will "dial into" any SOMESERVER that "dials home" using SSH.
Create a "dial home" client program (DIAL_HOME_CLIENT) for SOMESERVER which is downloaded as part of a package
Part 2: The Proxy Server
Create a ssh to telnet proxy server program (PROXY_SERVER) for SOMESERVER which listens for connections from MYPC and funnels them into a telnet connection to DEVICE(x).
Thanks to Greg Hewgill, it sounds like I can use Paramiko to pull together the PROXY_SERVER code on SOMESERVER. It appears that Paramiko also requires PyCryto, and the Windows binary for it can be found here.
Future Robustness
At a future date, the telnet connection will be replaced with an SSH client (dropbox on DEVICE(x)).
In Closing
I think the above will allow MYPC to connect "seamlessly", but the details of how to put together these programs is unknown to me. I already know how to package up a python program using Innosetup and/or py2exe. What I'd love to see is links pointing to different pieces of the solution so I can pull it all together. And then I can post it.
Thanks in advance!
I have to admit that I didn't quite follow all of your description, especially the "dial home" client/server part. However, your diagram seems sufficient for understanding.
Set up port forwarding on "router2" that forwards the incoming SSH port to your Windows server.
Write a Python program (you will probably find paramiko helpful) that runs on your Windows server, listens for SSH connections, and opens a telnet connection to one of your devices on the back end.
That seems sufficient to me. If you've got weird restrictions on the Windows server about only being able to run an executable once before it is deleted, that seems like another problem to solve that doesn't really relate to this tunnelling problem.