I have a java code which makes connection to a Java RMI server - lookup followed by method invocation.
Both machine are under the same firewall in onpremise and works as expected.
When my client/java moved to AWS, the RMI server is still running in on-premise.. But here in this case, it fails with below error..
Lookup success, method call failed..
Lookup for Remote Object Successful.
ErrorMessage:startupFunction : RemoteException Caught.. Connection refused to host: XXXXX ; nested exception is:
java.net.ConnectException: Connection timed out
PS : I see similiar issue in this post, but nothing seems to work in my case
You need to export your remote object on a fixed port, and open that port in your firewall.
Fixed this by adding the port used by RMI Method.. We ran the request from on-premise and in the RMI host we ran netstat and captured the port list.. This way we could figure out the port and enabled in Security group in AWS.. thanks all for your help..
Related
Launch error: Failed to connect to remote VM. Connection timed out
Project -SDK
Connection type - Standard (Socket Attach)
Host: IP address of the SAP server
Port: 8080
There is nowhere like enough information in your question to identify the actual cause of your problem (or the fix), but problems like this typically occur because:
you are using the wrong hostname or IP address when connecting to the server
the server is off
a firewall is blocking your access to the server
there is something wrong with the network.
Hope this will give you some ideas about what to look for.
I am still facing this problem for about 2 days already. It seems I did some researched on Google and as well stack overflow. I followed step by step but still not running.
-> Enable SQL BROWSER
-> Enable TCP/IP PORT and change to 1433
I tried both but still not working. It still giving me this error.
Exception in thread "main" com.microsoft.sqlserver.jdbc.SQLServerException: The connection to the host ., named instance sqlexpress has failed. Error: "java.net.UnknownHostException: .". Verify the server and instance names, check that no firewall is blocking UDP traffic to port 1434, and for SQL Server 2005 or later verify that the SQL Server Browser Service is running on the host.
This is my connection code:
Connection conn = DriverManager.getConnection("jdbc:sqlserver://.\\sqlexpress;user=sa;password=;database=pharmacy_posic");
My server name: .\sqlexpress
My Username : sa
My password : (blank)
Am I making any mistake on the connection?
Check this it is explained very well:
https://www.youtube.com/watch?v=Z46OHxdEEEI
When I print the I.P. address of the system using InetAddress.getLocalHost(), I get user-VAIO/192.168.1.3 . Now, when I connect to derby using jdbc:derby://localhost:1527/mydatabase;create=true, it connects without any errors but when I connect the same using jdbc:derby://192.168.1.3:1527/mydatabase;create=true, it fails giving me the following exception:-
java.net.ConnectException : Error connecting to server 192.168.1.3 on port 1527 with message Connection refused: connect.
Any help will be appreciated.
When you start your Derby Network Server, you provide a value for the '-h' argument. You might not realize you are doing this, if you are using the packaged StartNetworkServer.bat file, but look inside the batch file, and you will see the -h argument there.
The batch file comes provided with the syntax '-h default' when you download Derby from the Apache website.
But you can change that, to say, for example, '-h 192.168.1.3', and then your Derby Network Server will accept connections that specify 'jdbc:derby://192.168.1.3/my/database'.
Note that if you want to accept such connections from other computers on the network, you will also have to adjust your Windows Firewall rules, as by default it will prevent such connections.
Today I encountered the following problem. When connecting to a database, the following error.Appeal to the remote database by connecting through vpn.
Added necessary firewall ports and even tried to disconnect its(did not help)
Added record to $JAVA_HOME/jre/lib/security/java.policy
grant codeBase "file:/-" {
permission java.security.AllPermission;
};(did not help)
If trying to connect with same data through sql management studio, it works and there is access. from the development environment no connection
Example(string connection = jdbc:sqlserver://DEVMSSQL14.test.com:1433;SCHEMA=test;DATABASENAME=test, sql managment studia = DEVMSSQL14.test.com,1433)
on another computer it works without problems, the same version of the project
It remains only to "Permission denied: connect".Maybe somebody faced with similar
Error:
The TCP/IP connection to the host DEVMSSQL14.test.com, port 1433 has failed. Error: "Permission denied: connect. Verify the connection properties. Make sure that an instance of SQL Server is running on the host and accepting TCP/IP connections at the port. Make sure that TCP connections to the port are not blocked by a firewall.".
In the error message, you have shown like DEVMSSQL14.test.com, 1433 has failed.
I believe, it is correct. I dont think. this host name is correct. which says "TEST" as domain
Open the cmd, try to ping DEVMSSQL14.test.com
Success case :
If you are able to ping, then make sure the services are running for sql in services
Failure case:
Get the right host name to establish the connection
When i tried, i got this message, because i may be out of network.
Pinging DEVMSSQL14.test.com [208.64.121.161] with 32 bytes of data:
Request timed out.
Request timed out.
Try setting a System Property while running the code.
The catch is to introduce this line in code: System.setProperty("java.net.preferIPv4Stack", "true");
Or to pass it in VM option: -Djava.net.preferIPv4Stack=true
I can SSH and PING a machine running Fedora 18, but whenever I try connect to it using Sockets, I get NoRouteToHostException (I tried Java and C++, and I get the same error).
Any ideas? I have looked around but could not find a solution that works.
If you're not trying to connect to the same port that ssh(1) uses (port 22) then the problem could be that a firewall exists between you and the destination and it doesn't allow your packets through. You can test this by having your code try to connect to port 22 on the destination host. If you don't get the same exception, then this is the likely cause.
You should also verify that your code is OK by having it try to connect to the local host (i.e., the computer on which it's running). You should not get the no-route-to-host exception (unless the firewall on the local host is doing something odd)