telnet: connect to address xxx.x.x.x: Connection refused

Hi,

I just wrote and ran a PHP socket server, but the telnet connection was refused.

The SSH/Telnet command used:
$ /usr/bin/php -q socketserver.php
telnet xxx.x.x.x 9000

The socketserver.php script:

<?php
// Set time limit to indefinite execution
set_time_limit (0);

// Set the ip and port we will listen on
$address = 'xxx.x.x.x';
$port = 9000;

// Create a TCP Stream socket
$sock = socket_create(AF_INET, SOCK_STREAM, 0);
// Bind the socket to an address/port
socket_bind($sock, $address, $port) or die('Could not bind to address');
// Start listening for connections
socket_listen($sock);

/* Accept incoming requests and handle them as child processes */
$client = socket_accept($sock);

// Read the input from the client – 1024 bytes
$input = socket_read($client, 1024);

// Strip all white spaces from input
$output = ereg_replace("[ \t\n\r]","",$input).chr(0);

// Display output back to client
socket_write($client, $output);

// Close the client (child) socket
socket_close($client);

// Close the master sockets
socket_close($sock);
?> 

PHP:

Please help,

Thanks

 

Can you firstly verify if the script is actually listening on that port? Try using netstat to see if this is true:

netstat -nap | grep LISTEN

 

How to use netstat? It's an apache server, I tried the command using SSH, but:

Sorry for being dumb..

 

Just log into the server with SSH and type at the command prompt:
netstat -tulpen | grep LISTEN

If your server is actually running and listening on port 9000 you should see a line with an
IP followed by :9000.

 

Yes, I did. But the result is:
-sh: netstat: command not found

 

ok, please make sure that you are root and that netstat is installed, e.g. try
whereis netstat

 

What do you mean? type "whereis netstat" at the command prompt?

I am at root, not sure if netstat is installed..

Thanks

 

yes exactly, type the following commands at the shell command prompt and let me know the output:
whoami
whereis netstat

It would be helpful to know the system you are running, Gentoo, Debian, BSD or ...

 

whoami worked, whereis didn't.
-sh: whereis: command not found

The server type is Apache/2.0.52 (Red Hat)

Thanks

 

what was the output of whoami ?

 

Do this :

/bin/netstat -a | grep 9000

If you receive /bin/netstat not found then there is a problem with your server I've ran 1,000s of red hat servers in my live and have never seen one without netstat installed. It should be part of the core install.

 

It output my user name.

$ /bin/netstat -a | grep 9000
-sh: /bin/netstat: No such file or directory

I forgot to mention it's a virtual dedicated server.

Thanks

 

You say that it output your username. So I assume you are not root? Type
su -
to become root, then verify with whoami and try again with netstat.
When you type
ls -lha /bin
is there a line with netstat ?

 

$ su -
-sh: su: command not found

I can't find a line with netstat
ls -lha /bin

 

This is a bit strange, netstat and su should be available on the system. Have you noticed other strange behaviour of your server recently? Missing logs, crashed apps, unknown files, unusual amount of traffic or similar things?
Does "su root" work, without the dash?

Another way is to start your server and then type
ps auxf
Look for a line which contains socketserver.

You could install nmap if it isn't already installed and then run
nmap localhost
to list the open ports

 

I don't find any strange behaviour of the server.

"su root" didn't work either.. Tried "ps auxf" but there is no socketserver.

 

if you started the server before your "ps auxf" and there is no line for it this simply means that the server is not running and thus the port 9000 is not open. That's why you can't connect with telnet.

The code you posted looks a bit like it just runs through and finishes while it should run permanently like a daemon. You should check the PHP docu to find instructions how to write a permanently running server. The examples I found there contain "endless" while loops for example.

http://www.php.net/manual/pl/function.stream-socket-server.php

 

...
Just found what you need:
http://devzone.zend.com/node/view/id/1086#Heading7

 

Thanks norbert, I will test it, but how do I stop it using SSH?

 

As soon as you have a running server and find it with ps auxf look in the column "PID" which is the Process ID. Let's say it is 4281. Then you stop it with
kill 4281
or
kill -9 4281