Can't connect to localhost server - connection request failed

Questions & Answers
1

Hey everyone. Hoping someone might have an answer for what seems like a pretty ridiculous problem. I think I’ve read every answer related to this in here about 10 times, trying to find a solution.

Basically, I can’t connect to a server hosted on localhost, from localhost. i.e. I have a server and client both running on the same machine, and the client just errors "the connection request to 127.0.0.1:whateverport failed. Are you sure the server can be connected to.

I’ve watched about six different client/server tutorials on YT, and I can’t see what I’m doing wrong. The only difference is that most tutes use the same application as client/server, whereas I have two separate applications.

I have tried:

  • -run in background on/off for client and server and server only.
  • -multiple different port numbers
  • -connecting via LAN IP instead of “localhost” or “127…”
  • -connecting via public IP
  • -creating rules in windows firewall
  • -turning off windows firewall
  • -initialisation NAT param set to false, true, and removed (though I get an obsolete warning about that last)
  • -running 32 and 64 bit versions of the server
  • Adding the connect code to be triggered by a keypress instead of in the Start()

I just don’t know what else to do. The one thing I know I haven’t tried is using Unity’s Master Server, but I didn’t want to do this - seems highly unnecessary.

So time for some code.
Server:

using UnityEngine;
using System.Collections;

public class RemNetwork : MonoBehaviour {

	public GUIText updateScreen;


	void Start() {
		updateScreen.text = updateScreen.text + "

Server started. Initialising…

";
LaunchServer ();
}

	void LaunchServer() {
		//Network.incomingPassword = "test";
		Network.InitializeServer(16, 25003);
	}

	void OnServerInitialized() {
		updateScreen.text = updateScreen.text + "Server Initialised

";
}

	public void OnGUI()
	{
		if (Network.peerType == NetworkPeerType.Server)
		{
			GUI.Label(new Rect(300,100,400,30), "Clients connected: " + Network.connections.Length ); 
		}
	}}

Client: (in here I connect in the Start() function)

void Start () {
		Network.Connect ("localhost", 25003);
		if (Network.isClient) 
		{
			Debug.Log ("Connected");
		} 
		else 
		{
			Debug.Log ("Not connected");
		}

	}

The network.isclient bit doesn’t really work since it gets called before the connection can be established, but regardless, I quickly get the connection request failed message.

The server “works” as far as I can tell. It starts, it initialises, it lists connections as 0.

So currently, at a loss. Knowing my luck it’s just something stupid. In the meantime I guess I’ll give up and try using a master server implementation, but again, I’d really like not to have to do this.

Thanks in advance for any help you can provide!

2

This may sound obvious, but have you forced both server- and client-side password entries to “”? I see an entry commented out on the svr side, but nothing on the clientside to indicate you’ve tried this…

3

Connections are not instantly established. You should move the check for connection to other place, like to Update. I would also change “localhost” to “127.0.0.1” just to be sure.

To check the connection you can use the OnConnectedToServer and OnDisconnectedFromServer methods.

private bool connected = false;

void Start () {
    Network.Connect("127.0.0.1", 25003);
}

void OnConnectedToServer() {
    connected = true;
}

void OnDisconnectedFromServer() {
    connected = false;
}

void OnGUI() {
    GUI.Label(new Rect(300,100,400,30), "Connected: " + (connected == true));
}

Hope this helps!

4

Hi guys, sorry I haven’t been able to get back to testing this out, but have solved the problem. Well, to be specific, I haven’t, but the problem is in my PC, somewhere. I ran the client and server on my laptop and it worked first time. Still does not run on my desktop (frustrating).

So there’s a config issue, or a conflict with something… who knows!
The point is, the code was fine, I just need to find where/what on my PC is causing the problem. Or work permanently from my laptop. (ugh)

So anyway, thanks for your suggestions - I did toy with them first before deciding to try another machine. :slight_smile: