Connecting to server
Trying to reconnect in 5 seconds
Error: Connection to server lost...
Connecting to server
Error, could not connect to server
Trying to reconnect in 5 seconds
Connecting to server
Error, could not connect to server
Trying to reconnect in 5 seconds
Connecting to server
Trying to reconnect in 5 seconds
Error: Connection to server lost..
Either your antivirus/firewall blocks connection from your PC to the server, or the server doesn't accept incoming connections. This might be your issue.
Edit: I'm assuming you're using the correct IP/address for the server, that would be the first thing to check.
Related
I have created simple TCP server which accepts connections and request and do some processing. I have referred following example and it is working fine. I send data to to connected client continuously and it is being printed on client side. Though after around period of 20-25 minutes, the client stops receiving any data. Also after such incident, the server shows running but now when I connect my client again to server, the server's connection accept handler doesnt get invoked. But I am able to telnet to the server's port and client is able to connect. Any idea what might be the problem?
sorry for the noobish question but I can't find any resources online clearly stating whether this should work or not, and all tutorials / sample code always use localhost ^^ Soooo...
I'm trying to setup a simple server / client using RakNet. I'm literally just following the first tutorial (http://www.jenkinssoftware.com/raknet/manual/tutorial.html), just trying to get the client to connect to the server and keep the connection alive for a bit.
It all works great as long as I use 127.0.0.1 or 192.168.0.XXX, I can start the server, then the client, the server detects the connection request and sends the reply to the client, the client receives the reply and prints out "connection accepted" and such, and I can exchange messages between the client and the server.
However if I try using my actual IP, the server does not seem to detect the connection request (if you look at the tutorial code, it doesn't print "incoming connection"), but the client still receives a reply from somewhere ("Our connection request has been accepted").
After this initial semi-successful connection, no more packets will be received by either server or client, and the client will inevitably get disconnected after a few seconds (I assume time out?).
Port is open on the router, and the app runs fine as long as I keep it on localhost.
So my question is: is it even possible to run a server and client on the same machine / IP which is sitting behind a router?
The RakNet documentation part about NAT punchthrough and UDP forwarding does mention no more than one client and server being able to run on the same machine, but I was under the impression that one server / one client would not be an issue?
Thanks in advance to anybody who can shed some light on this!!
Forgot to mention my firewall is disabled !
I have client server application that works with Firebird server. Everytime when clients connect to the server they(client apps) don't check if there is a network connection to the server so at this time my application sometimes freezes when the server computer is switched off or service has stopped, so first of all I need to check connection if remote host is switched on or at some port anything listening....
Before establishing the connection I need to check it and make sure server and service is running using Indy components.
Any ideas? also I can use IcmpClient to ping remote host and then establish connection but which is the most optimal way ?
If you just want to check if the server computer can be reached, you could do a "ping" to check that. However, if you want to check if a specific TCP port is open, then the only way to find that out is to actually do a proper connect, which leads to the "freezing" program while the connection times out if there is no-one listening on that port.
I have implemented a design in C++ that is:-
I parse an XML file which contain the ip and port of several servers,for each ip and port i first call the connect to server function in which i make a TCP socket connection with the server whether the connection is established or not i make a thread for each ip and port,if connection is not established i send the status of the server that connection is not established and if connection is established i then make a request to the server and receive response from the server in the thread.This is done after every minute for each thread.
Now the problem that i am facing is,if connection terminates or if the server power goes,how to again make a connection i mean after every one minute before sending request and receiving response from the server i have to check whether the connection is still there or not.
Can you please tell me how to do that?
You could have whatever it is that checks the connection status also do all of the communication for your other classes. Other classes pass a function pointer to it and in that method you test the connection, and if it's successful run the function you've been passed. If not stick it on a queue to be run once the connection is re-established.
I have an application which connects a remote database server.
If mysql server stops for a reason and stars succesfully after that, my application cannot detect server status quickly. It takes nearly 20 seconds to reconnect to the database server. So my gui freezes. I do not want a gui freeze for 20 seconds
So far I tried
mysql_ping
mysql_real_connect
functions
MYSQL_OPT_RECONNECT
MYSQL_OPT_CONNECT_TIMEOUT
options
My enviroment is not multi-threaded. So
how to do a faster detection?
If you do networking synchronously, be prepared for freezes. For this very reason it makes sense to do data-manipulation in a separate thread.
You could try telnet to the mysql port (usually 3306). If you get a connection refused, mysql isn't listening.
Working.
root#XXXXXX:~# telnet localhost 3306
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
L
5.6.4-m7)#m#_8:W�hP5YBzaXs[MOmysql_native_password
Down.
root#XXXXXX:~# telnet localhost 3306
Trying 127.0.0.1...
telnet: Unable to connect to remote host: Connection refused
The refused message is almost instant.
As already discussed by others, i won't talk about using multiple threads or processes. Can you connect to your mysql server on tcp? That way in most scenario's you would receive a tcp fin immediately to indicate a closed connection, though at times this might not be the case even. But most robust applications do a proper close.
shell> mysql --protocol=TCP
MYSQL how to specify protocol
If server doesn't accept it, i believe it can be enabled from config settings.
However, this does not address scenarios such as server suddenly gets off the network, or you client's connection is down etc.