Allowing connections outside of LAN

[ben1996123]

I've got a client which can connect to a server, and it works fine when the server is running in LAN, but if a client outside LAN tries to connect to the server, it doesn't allow it to connect. I have forwarded the port that the server uses to my ipv4 address but it still won't allow the connection.
How can other clients connect to my server?

[prof.ebral]

Have you forwarded the port through the firewall AND the router?

[ben1996123]

I disabled my firewall and it still didn't work. Also, when I go to the firewall settings, there is no option to forward a port, only to allow another program.

[prof.ebral]

AND router? Your port needs to be forwarded through your router also. Test here: http://www.yougetsignal.com/tools/open-ports/

You shouldn't need to turn your firewall off. That shows a basic misunderstanding how the firewall works. You should read on how to open a port in your firewall.

[anda_skoa]

Did you bind the port on the external interface or on all interfaces? Maybe it is just bound in the loopback device (thus allowing local connections)?

Cheers,
_

[ben1996123]

AND router? Your port needs to be forwarded through your router also. Test here: http://www.yougetsignal.com/tools/open-ports/

You shouldn't need to turn your firewall off. That shows a basic misunderstanding how the firewall works. You should read on how to open a port in your firewall.

Ok, I turned my firewall back on and opened the port that I need. I've also forwarded the port on my router but it still won't let anyone connect.

[prof.ebral]

If the test tool I showed shows your port as open, then you have a problem in the code. Can you show us some of your code? Perhpas anda_soka's suggestion has relevence to your problem.

[ben1996123]

If the test tool I showed shows your port as open, then you have a problem in the code. Can you show us some of your code? Perhpas anda_soka's suggestion has relevence to your problem.

The test tool said the port is closed when I entered my external IP address and my local IPv4 address.

Here's the server code:

main.cpp:

#include <QtCore/QCoreApplication>
#include "myserver.h"
 
int main(int argc, char *argv[]){
    QCoreApplication a(argc, argv);
    myserver server;
    server.startServer();
    return a.exec();
}

#include <QtCore/QCoreApplication>
#include "myserver.h"

int main(int argc, char *argv[]){
    QCoreApplication a(argc, argv);
    myserver server;
    server.startServer();
    return a.exec();
}

To copy to clipboard, switch view to plain text mode 

myserver.h:

#ifndef MYSERVER_H
#define MYSERVER_H
 
#include <QtNetwork/QTcpServer>
#include <QDebug>
#include <iostream>
#include "mythread.h"
 
class myserver : public QTcpServer
{
    Q_OBJECT
public:
    explicit myserver(QObject *parent = 0);
    void startServer();
 
protected:
    void incomingConnection(int socketDescriptor);
 
};
 
#endif // MYSERVER_H

#ifndef MYSERVER_H
#define MYSERVER_H

#include <QtNetwork/QTcpServer>
#include <QDebug>
#include <iostream>
#include "mythread.h"

class myserver : public QTcpServer
{
    Q_OBJECT
public:
    explicit myserver(QObject *parent = 0);
    void startServer();

protected:
    void incomingConnection(int socketDescriptor);

};

#endif // MYSERVER_H

To copy to clipboard, switch view to plain text mode 

myserver.cpp:

#include "myserver.h"
 
myserver::myserver(QObject *parent) :
    QTcpServer(parent)
{
}
 
void myserver::startServer(){
    if(!this->listen(QHostAddress::Any,1234)){
        qDebug() << "Server failed to start";
    }
    else{
        qDebug() << "Server started";
    }
}
 
void myserver::incomingConnection(int socketDescriptor){
    mythread *thread = new mythread(socketDescriptor, this);
    connect(thread,SIGNAL(finished()),thread,SLOT(deleteLater())); //deletes the thread after its finished being used
    thread->start();
}

#include "myserver.h"

myserver::myserver(QObject *parent) :
    QTcpServer(parent)
{
}

void myserver::startServer(){
    if(!this->listen(QHostAddress::Any,1234)){
        qDebug() << "Server failed to start";
    }
    else{
        qDebug() << "Server started";
    }
}

void myserver::incomingConnection(int socketDescriptor){
    mythread *thread = new mythread(socketDescriptor, this);
    connect(thread,SIGNAL(finished()),thread,SLOT(deleteLater())); //deletes the thread after its finished being used
    thread->start();
}

To copy to clipboard, switch view to plain text mode 

mythread.h:

#ifndef MYTHREAD_H
#define MYTHREAD_H
 
#include <QThread>
#include <QtNetwork/QTcpSocket>
#include <QDebug>
 
class mythread : public QThread
{
    Q_OBJECT
public:
    explicit mythread(int id, QObject *parent = 0);
    void run();
 
public slots:
    void disconnected();
    void readyRead();
 
signals:
    void error(QTcpSocket::SocketError socketError);
 
private:
    QTcpSocket *socket;
    int socketDescriptor;
 
};
 
#endif // MYTHREAD_H

#ifndef MYTHREAD_H
#define MYTHREAD_H

#include <QThread>
#include <QtNetwork/QTcpSocket>
#include <QDebug>

class mythread : public QThread
{
    Q_OBJECT
public:
    explicit mythread(int id, QObject *parent = 0);
    void run();

public slots:
    void disconnected();
    void readyRead();

signals:
    void error(QTcpSocket::SocketError socketError);

private:
    QTcpSocket *socket;
    int socketDescriptor;

};

#endif // MYTHREAD_H

To copy to clipboard, switch view to plain text mode 

mythread.cpp:

#include "mythread.h"
 
mythread::mythread(int id, QObject *parent) :
    QThread(parent)
{
    this->socketDescriptor = id;
}
 
void mythread::run(){
    socket = new QTcpSocket();
    if(!socket->setSocketDescriptor(this->socketDescriptor)){
        emit error(socket->error());
        return;
    }
 
    connect(socket,SIGNAL(disconnected()),this,SLOT(disconnected()),Qt::DirectConnection);
    connect(socket,SIGNAL(readyRead()),this,SLOT(readyRead()),Qt::DirectConnection);
 
    qDebug() << "client" << socketDescriptor << "connected";
    exec(); //stop thread from closing
}
 
void mythread::readyRead(){
    QByteArray data = socket->readAll();
    qDebug() << "client" << socketDescriptor << "sent" << data;
    if(data == "J"){
        socket->write("hello");
    }
}
 
void mythread::disconnected(){
    qDebug() << "client" << socketDescriptor << "disconnected";
    socket->deleteLater();
    exit(0);
}

#include "mythread.h"

mythread::mythread(int id, QObject *parent) :
    QThread(parent)
{
    this->socketDescriptor = id;
}

void mythread::run(){
    socket = new QTcpSocket();
    if(!socket->setSocketDescriptor(this->socketDescriptor)){
        emit error(socket->error());
        return;
    }

    connect(socket,SIGNAL(disconnected()),this,SLOT(disconnected()),Qt::DirectConnection);
    connect(socket,SIGNAL(readyRead()),this,SLOT(readyRead()),Qt::DirectConnection);

    qDebug() << "client" << socketDescriptor << "connected";
    exec(); //stop thread from closing
}

void mythread::readyRead(){
    QByteArray data = socket->readAll();
    qDebug() << "client" << socketDescriptor << "sent" << data;
    if(data == "J"){
        socket->write("hello");
    }
}

void mythread::disconnected(){
    qDebug() << "client" << socketDescriptor << "disconnected";
    socket->deleteLater();
    exit(0);
}

To copy to clipboard, switch view to plain text mode 

[prof.ebral]

The test tool said the port is closed when I entered my external IP address and my local IPv4 address.

Then your port isn't forwarded properly. Use your external IP address. There is a link underneath that you can click to fill the entry with your current IP address. The issue is likely your router at this point. Some routers are funky when it comes to port forwarding. My DLink router oddly doesn't forward ports externally .. only internally. But it does have a virtual server option that allows me to forward the port externally.

Whatever the case may be, make sure your port appears as open to an external tool like the one I gave you. There is no point in checking code until you can confirm the port is visibly open the outside.

[ben1996123]

Then your port isn't forwarded properly. Use your external IP address. There is a link underneath that you can click to fill the entry with your current IP address. The issue is likely your router at this point. Some routers are funky when it comes to port forwarding. My DLink router oddly doesn't forward ports externally .. only internally. But it does have a virtual server option that allows me to forward the port externally.

Whatever the case may be, make sure your port appears as open to an external tool like the one I gave you. There is no point in checking code until you can confirm the port is visibly open the outside.

Hmm... I've tried forwarding it to my internal and external IP addresses and it still says the port is closed. Just to test it, I tried the test tool with port 80 and it still said the port is closed...

[prof.ebral]

Port 80 is in use by your browser. Look: http://traipsemeta.madmathlabs.info/ That is the meta server I run for the OpenRPG virtual game table software. This is my IP and port 64.21.252.156:9558 ... Port 9558 is open.

[ben1996123]

Port 80 is in use by your browser. Look: http://traipsemeta.madmathlabs.info/ That is the meta server I run for the OpenRPG virtual game table software. This is my IP and port 64.21.252.156:9558 ... Port 9558 is open.

Ok, well I just tried port 25565 from minecraft in the test tool which I know is open and it works, but the test tool still says its closed... Maybe I'm just doing something completely wrong...