Port testing on Linux or AIX

Sometimes, I need to test, if firewall order is OK and port is properly open and service is not installed yet.
On Linux, it’s not a big deal, because there is installed
Python by default, so you can use this command:

python -m SimpleHTTPServer 80

But on AIX or different platform Python is not installed by default, so I found on internet simple Java server and my colleague (thanks Lukas) did some tuning there.. save following code as TCPServer.java (or you can find source here):

import java.io.*;
import java.net.*;
public class TCPServer
public static void main(String argv[]) throws Exception
ServerSocket welcomeSocket = new ServerSocket(3001);
Socket connectionSocket = welcomeSocket.accept();
new Thread(new TCPServer(). new Client(connectionSocket)).start();
public class Client implements Runnable{
Socket client;
String clientSentence;
String capitalizedSentence;
public Client(Socket s){
client = s;
public void run(){
BufferedReader inFromClient =
new BufferedReader(new InputStreamReader(client.getInputStream()));
DataOutputStream outToClient = new DataOutputStream(client.getOutputStream());

while((clientSentence = inFromClient.readLine())!=null){
System.out.println("Received: " + clientSentence);
capitalizedSentence = clientSentence.toUpperCase() + '\n';
}catch(Exception e){e.printStackTrace();}

Then type following command to compile it:
javac TCPServer.java

And run it:
java TCPServer

That’s all.

Python3 HTTPS

Create a certificate

openssl req -new -x509 -keyout python-cert.pem -out python-cert.pem -days 365 -nodes


import http.server, ssl

server_address = ('', 443)
httpd = http.server.HTTPServer(server_address, http.server.SimpleHTTPRequestHandler)
httpd.socket = ssl.wrap_socket(httpd.socket,

Update: If you are Perl-like guy, you can use this code from Petr.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.