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Connection failed with racer reasoner

I'm trying to use racer (Description Logic reasoner), but i get the following error
com.racersystems.jracer.RacerClientException: Connection refused: connect
at com.racersystems.jracer.RacerClient.openConnection(RacerClient.java:76)
at test.Test.main(Test.java:12)
the code i'm executing is the following :
package test;
import com.racersystems.jracer.*;
public class Test {
public static void main(String[] argv) {
String ip = "127.0.0.1";
int port = 8088;
String filename="\"/jracer-2-0.zip_expanded/jracer-2-0/demo/people+pets.owl\"";
RacerClient racer = new RacerClient(ip,port);
try {
racer.openConnection();
System.out.println(racer.sendRaw("(owl-read-file " + filename + ")"));
System.out.println(racer.sendRaw("(all-atomic-concepts)"));
racer.closeConnection();
}
catch (Exception e) {
e.printStackTrace();
}
}}
I don't know who to solve it ?
Any suggestions ?

You are apparently trying to connect to a service that is running on the same machine as you are running the program ... using the 127.0.0.1 loopback interface.
The fact that it is giving you a "connection refused" response means that the service is not currently running on "this machine" or the port that you have specified.
The solution will be to ensure that the service is running and listening on the specified IP and port; e.g. check the IP address and port, and start or restart the service.

"com.hierynomus.mssmb2.SMBApiException: STATUS_ACCESS_DENIED: Authentication failed ..." on authenticate call

I'm trying to connect to an SMB server using com.hierynomus.smbj v0.10.0. Connection is ok but as soon as I try to authenticate I'm getting this exception:
com.hierynomus.mssmb2.SMBApiException: STATUS_ACCESS_DENIED (0xc0000022): Authentication failed for 'USERNAME' using com.hierynomus.smbj.auth.NtlmAuthenticator#4152d38d
at com.hierynomus.smbj.connection.Connection.authenticate(Connection.java:194)
at MyTest.smbj(MyTest.java:...)
Here is the test code to see what I'm doing:
#Test
void smbj() throws Exception {
SMBClient client = new SMBClient();
try (Connection connection = client.connect("my-smb-server.de")) {
AuthenticationContext ac = new AuthenticationContext("USERNAME", "PASSWORD".toCharArray(), "DOMAIN");
Session session = connection.authenticate(ac);
// ... do more here ...
}
}
The SMB server and connection is perfectly fine since I'm able to connect from the same machine the test is running using multiple GUI tools (e.g. ForkLift) without any customized settings.
connection.getConnectionInfo() returns this before doing the authentication:
Successfully connected to: my-smb-server.de
ConnectionInfo{
serverGuid=975b39d3-55c0-4490-84e7-80371b734ce7,
serverName='my-smb-server.de',
negotiatedProtocol=NegotiatedProtocol{dialect=SMB_2_1, maxTransactSize=8388608, maxReadSize=8388608, maxWriteSize=8388608},
clientGuid=85863c1f-0328-4c21-9a72-b3d907b23a1d,
clientCapabilities=[SMB2_GLOBAL_CAP_DFS],
serverCapabilities=[SMB2_GLOBAL_CAP_DFS, SMB2_GLOBAL_CAP_LEASING, SMB2_GLOBAL_CAP_LARGE_MTU], > clientSecurityMode=0,
serverSecurityMode=3,
server='null' }
Any help is highly appreciated.

rabbitmq, Java client works via SSL, but .NET one does not

I’m new to rabbitmq but I have to connect to remote broker to send and receive messages. Remote server is out of my control and it’s almost impossible to get answers from its team. Nevertheless, I have address, port, virtual host and user credentials at my disposal. Server uses TLS v1.2.
The problem is I cannot establish connection to the server with .NET client. Client is “rabbitmq.client.5.1.0”, .NET Framework 4.5.1 and VS 2017. My code is:
public bool Start() {
try {
var f = new ConnectionFactory();
f.UserName = "TestUser";
f.Password = "TestPwd";
f.HostName = "x.x.x.x";
f.Port = 5673;
f.VirtualHost = "TestVH";
f.Ssl.Version = SslProtocols.Tls12;
f.Ssl.Enabled = true;
f.Ssl.AcceptablePolicyErrors = SslPolicyErrors.RemoteCertificateChainErrors
| SslPolicyErrors.RemoteCertificateNameMismatch
| SslPolicyErrors.RemoteCertificateNotAvailable;
var c = f.CreateConnection();
} catch( Exception e ) {
throw e;
}
}
It throws an exception which innermost is:
Authentication failed because the remote party has closed the transport stream.
(Wireshark capture).
If I do it with Java (1.8, amqp-client-4.0.2), I can successfully connect to the server.
public static void main( String[] args ) throws Exception{
ConnectionFactory factory = new ConnectionFactory();
factory.setHost("x.x.x.x");
factory.setPort(5673);
factory.setUsername( "TestUser" );
factory.setPassword( "TestPwd" );
factory.setVirtualHost( "TestVH" );
factory.useSslProtocol("TLSv1.2");
Connection conn = factory.newConnection();
}
Wireshark capture
I would like to use C# to get the job done but I can not sort this thing out. Any help would be greatly appreciated!

try changing this line:
f.Ssl.Version = SslProtocols.Tls12;
to this:
f.Ssl.Version = SslProtocols.Tls12 | SslProtocols.Ssl3 | SslProtocols.Tls11 | SslProtocols.Ssl2;
If that works then you narrow them down

Java RMI connection over internet

I'm trying to get remote objects from a server hosted on different network. I'm able to connect on same machine and on same network, but when I try to get it from different network I get:
Connection refused to host: 192.168.1.131; nested exception is: java.net.ConnectException: Connection timed out: connect
It seems that lookup function is searching at wrong network. I tried to use System.setProperty but it doesn't work. Here the code:
Server
public class Main {
public static void main(String[] args) {
try{
System.out.println("Init server...\n");
TestInterface test = new TestImplement();
System.setProperty("java.rmi.server.hostname", "95.247.x.x");
System.out.println("Reg RMI...\n");
Registry rmiRegistry = LocateRegistry.createRegistry(5555);
rmiRegistry.rebind("Test" , test);
System.out.println("Reg completed!\n");
}catch(Exception e){
e.printStackTrace();
}
}
}
Client
...
registryRMI = LocateRegistry.getRegistry("95.247.x.x",5555);
TestInterface testClient = (TestInterface)registryRMI.lookup("Test");
...
Do I need to set java.rmi.server.hostname in client jar as well?

TestInterface test = new TestImplement();
System.setProperty("java.rmi.server.hostname", "95.247.x.x");
You need to set java.rmi.server.hostname before exporting any remote objects. Doing it afterwards is too late.
System.setProperty("java.rmi.server.hostname", "95.247.x.x");
TestInterface test = new TestImplement();

Java RMI client and remote server Connection Refused to localhost

I am not so experienced in Java RMI. I am trying to implement simple RMI communication, but faced with the problem.
Here my RMI client
public class MainClientApplication {
public static final String FILE_NAME_RMI_POLICY = "rmi.policy";
public static final String RMI_DOMAIN = "mydomain.net";
public static final String RMI_ENDPOINT = "/MD5Decrypter";
public static final String PROTOCOL = "rmi://";
public static void main(String[] args) {
System.out.println(System.getProperty("user.dir") + File.separator + FILE_NAME_RMI_POLICY);
System.setProperty("java.security.policy", System.getProperty("user.dir") + File.separator + FILE_NAME_RMI_POLICY);
String remoteHost = String.format("%s%s%s", PROTOCOL, RMI_DOMAIN, RMI_ENDPOINT);
System.setSecurityManager(new SecurityManager());
try {
ComputeEngine computeEngine = (ComputeEngine) Naming.lookup(remoteHost);
SwingUtilities.invokeLater(() -> new MainWindow("MD5 Decryption", computeEngine));
} catch (Exception ex) {
ex.printStackTrace();
}
}
}
Communication inerface
public interface ComputeEngine extends Remote {
Object executeTask(Task t) throws RemoteException;
}
My server
public class MainServer {
public static final int PORT = 1099;
public static final String RMI_ENDPOINT = "MD5Decrypter";
public static final String FILE_NAME_RMI_POLICY = "rmi.policy";
public static final String RMI_DOMAIN = "mydomain.net";
public static final String PROTOCOL = "rmi://";
public MainServer() {
try {
System.setProperty("java.security.policy", System.getProperty("user.dir") + File.separator + FILE_NAME_RMI_POLICY);
//System.setProperty("java.rmi.server.hostname", RMI_IP);
System.setProperty("java.rmi.server.hostname", RMI_DOMAIN);
System.setSecurityManager(new SecurityManager());
ComputeEngine computeEngine = new ComputeEngineExecutor();
// Naming.rebind(String.format("%s%s:%d/%s", PROTOCOL, RMI_DOMAIN, PORT, RMI_ENDPOINT), computeEngine);
Naming.rebind(RMI_ENDPOINT, computeEngine);
System.out.println("Successfully started RMI Server");
} catch (RemoteException e) {
e.printStackTrace();
} catch (MalformedURLException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
MainServer mainServer = new MainServer();
}
}
And rmi.policy
grant {
permission java.net.SocketPermission "*:1024-65535", "connect, accept";
permission java.io.FilePermission "-", "read";
permission java.net.SocketPermission "*:80", "connect";
};
So I have started rmiregistry on my server rmiregistry 1099. And everything works well until calling remote object method.
Here are my steps
Lets consider that my domain is mydomain.net , I host it on my server at home with static IP.
Run rmiregistry on the server
Run server application on the server
Run client application on any PC
Click button to invoke remote method
So it seems that everything connects and binds successfully, because if force enter invalid domain, endpoint or refused if rmiregistry is not started - java.rmi.ConnectException is thrown.
But when I try to invoke any method on remote object, BTW which has been already retrieved successfully it throws a java.rmi.ConnectException
java.rmi.ConnectException: Connection refused to host: 127.0.1.1; nested exception is:
java.net.ConnectException: Connection refused
at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:619)
at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:216)
at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:202)
at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:130)
at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(RemoteObjectInvocationHandler.java:227)
at java.rmi.server.RemoteObjectInvocationHandler.invoke(RemoteObjectInvocationHandler.java:179)
at com.sun.proxy.$Proxy0.executeTask(Unknown Source)
at ui.MainWindow.lambda$initGui$0(MainWindow.java:49)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2348)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
As I can understand the problem is that it (server) forces me to connect to my localhost instead of remote.
P.S on localhost everything works perfectly (both client and server on the one PC)
Please help to solve this problem.
EDIT
I have forgotten to tell that I have tried to set property of java.rmi.server.hostname, in this case it takes a lot of time to start the server and ends with exception.

Leaving the 127.0.0.1 issue aside, which is solved by java.rmi.server.hostname, your problem now is connect timeouts. This will be caused by your firewall. You need to export your remote object on a specific port, and you need to open that TCP port in your firewall.