I am trying to update the database table which is hosted on the server through MYSQL JDBC connector using eclipse.
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://49.**.***.115:3306/databasename";
String name = "user";
String password = "passs";
But I not able to connect to the database from my local machine. I checked all the information provided above are correct.
Can please some tell me what to i do next?
Here is the error:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1121)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:357)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2479)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2516)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2301)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:834)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:416)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:346)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at connecttoDB.getconnection(connecttoDB.java:27)
at updateDB.main(updateDB.java:17)
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:259)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:307)
... 16 more
Have you verified that you can connect to your database server from the machine you are running this code on? It looks like there is a network problem. A good idea as a first step to diagnosing MySQL connection problems is to always try connecting from the command line to rule out networking or credentials problems
mysql -uuser -p -h49.**.***.115 databasename
where "user" is the username "databasename" is the database and "49.**.***.115" is the ip of the database server.
check the following steps:
1- Ping the IP address to see if you can establish connection, There might be a firewall that is blocking incoming/outgoing communication.
2- Check that your ojdbc6/ojdbc14.jar is loaded in the same directory of your application.
Related
This is the code I have to test my db:
package mysql;
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.SQLException;
public class JDBCExample {
public static void main(String[] argv) {
System.out.println("-------- MySQL JDBC Connection Testing ------------");
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
System.out.println("Where is your MySQL JDBC Driver?");
e.printStackTrace();
return;
}
System.out.println("MySQL JDBC Driver Registered!");
Connection connection = null;
try {
connection = DriverManager
.getConnection("jdbc:mysql://192.99.148.171:3306/aldorps_aldorpva_donation","aldorps_donation", "stan1234");
} catch (SQLException e) {
System.out.println("Connection Failed! Check output console");
e.printStackTrace();
return;
}
if (connection != null) {
System.out.println("You made it, take control your database now!");
} else {
System.out.println("Failed to make connection!");
}
}
}
The error that I am receiving is:
-------- MySQL JDBC Connection Testing ------------
MySQL JDBC Driver Registered!
Connection Failed! Check output console
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 1.445.894.001.265 milliseconds ago. The last packet sent successfully to the server was 0 milliseconds ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2214)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:773)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:352)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at mysql.JDBCExample.main(JDBCExample.java:25)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet successfully received from the server was 1.445.894.001.261 milliseconds ago. The last packet sent successfully to the server was 0 milliseconds ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:341)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2137)
... 12 more
Caused by: java.net.ConnectException: Connection timed out: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:253)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:290)
... 13 more
Now I was thinking that it might be because port 3306 isnt open on my pc but that doesn't make much sense since this isn't being localhosted right?
Any of you guys any clue what to do?
java.net.ConnectException: Connection timed out: connect
Nothing to do with Java. This probably means there is a firewall in the way. See if you can Telnet to that host, port 3306, from the client.
I have installed Java 8 and I have the SchemaCrawler folder on E: on my machine. I run SQL Server 2012.
The cmd command used is below
sc.cmd -c graph -host=10.52.136.168 -user=sa -database=MyDBName schemacrawler.Main -infolevel=detailed -schemas=dbo -tabletypes=TABLE -outputformat=pdf -outputfile=database-diagram.pdf %*
I have checked the suggestions given here
but no luck . I still get the below error
schemacrawler.schemacrawler.SchemaCrawlerSQLException: Could not connect to jdbc
:hsqldb:hsql://10.52.136.168:9001/DeliveryIntelligence;readonly=true;hsqldb.lock
_file=false, with properties {user=sa}
at schemacrawler.schemacrawler.BaseDatabaseConnectionOptions.getConnecti
on(BaseDatabaseConnectionOptions.java:122)
at schemacrawler.schemacrawler.BaseDatabaseConnectionOptions.getConnecti
on(BaseDatabaseConnectionOptions.java:70)
at schemacrawler.tools.commandline.SchemaCrawlerCommandLine.execute(Sche
maCrawlerCommandLine.java:176)
at schemacrawler.tools.commandline.SchemaCrawlerMain.main(SchemaCrawlerM
ain.java:78)
at schemacrawler.tools.hsqldb.Main.main(Main.java:43)
Caused by: java.sql.SQLTransientConnectionException: java.net.ConnectException:
Connection refused: connect
at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
at org.hsqldb.jdbc.JDBCConnection.<init>(Unknown Source)
at org.hsqldb.jdbc.JDBCDriver.getConnection(Unknown Source)
at org.hsqldb.jdbc.JDBCDriver.connect(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at schemacrawler.schemacrawler.BaseDatabaseConnectionOptions.getConnecti
on(BaseDatabaseConnectionOptions.java:115)
... 4 more
Caused by: org.hsqldb.HsqlException: java.net.ConnectException: Connection refus
ed: connect
at org.hsqldb.ClientConnection.openConnection(Unknown Source)
at org.hsqldb.ClientConnection.initConnection(Unknown Source)
at org.hsqldb.ClientConnection.<init>(Unknown Source)
... 10 more
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at org.hsqldb.server.HsqlSocketFactory.createSocket(Unknown Source)
... 13 more
You are using SchemaCrawler for HyperSQL. Please download and use SchemaCrawler for SQL Server instead.
Sualeh Fatehi, SchemaCrawler
I got the below error when i try to connect remote database
I use mysql server 5.5,installed all jar files and ran grant previlidge scripts also,
Pls help me to resolve the same
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
Last packet sent to the server was 0 ms ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2120)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:723)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:302)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at JDBCExample.main(JDBCExample.java:31)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
Last packet sent to the server was 15 ms ago.
Caused by: java.net.ConnectException: Connection refused: connect
The error may be because you have not granted permission for remote location.Grant permission like this
GRANT ALL PRIVILEGES ON *.* TO 'root'#'192.168.1.205'
IDENTIFIED BY PASSWORD 'some_characters'
WITH GRANT OPTION;
FLUSH PRIVILEGES;
I am trying to connect to MySQL DB from Java over SSL using the following program.
public class MySQLJDBC {
public static void main(String[] args) throws ClassNotFoundException, SQLException {
Class.forName("com.mysql.jdbc.Driver");
String m_host = "localhost";
String m_port = "3306";
String m_db = "test";
boolean isSSL = true;
String dbUrl = "jdbc:mysql://" + m_host + ":" + m_port + "/" + m_db + "?noDatetimeStringSync=true&verifyServerCertificate=false&useSSL=" +String.valueOf(isSSL);
String m_user = "root";
String m_pass = "Pass";
System.setProperty("javax.net.ssl.keyStore","D:/content/dev/connectors/Database (JDBC)/2011.1/src/mykeystore.jks");
System.setProperty("javax.net.ssl.keyStorePassword","password");
System.setProperty("javax.net.ssl.trustStore","D:/content/dev/connectors/Database (JDBC)/2011.1/src/mystore.jks");
System.setProperty("javax.net.ssl.trustStorePassword","password");
DriverManager.getConnection(dbUrl, m_user, m_pass);
System.out.println(System.getProperty("javax.net.ssl.keyStore"));
}
}
If I have the client keystores installed, this will throw the following exception.
Exception in thread "main" com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
Last packet sent to the server was 328 ms ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2104)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:729)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:302)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:283)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at MySQLJDBC.main(MySQLJDBC.java:20)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
Last packet sent to the server was 328 ms ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
at com.mysql.jdbc.ExportControlled.transformSocketToSSLSocket(ExportControlled.java:102)
at com.mysql.jdbc.MysqlIO.negotiateSSLConnection(MysqlIO.java:4357)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1302)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2032)
... 12 more
Caused by: java.net.SocketException: Software caused connection abort: socket write error
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(Unknown Source)
at java.net.SocketOutputStream.write(Unknown Source)
at com.sun.net.ssl.internal.ssl.OutputRecord.writeBuffer(Unknown Source)
at com.sun.net.ssl.internal.ssl.OutputRecord.write(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.writeRecordInternal(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.writeRecord(Unknown Source)
at com.sun.net.ssl.internal.ssl.Handshaker.sendChangeCipherSpec(Unknown Source)
at com.sun.net.ssl.internal.ssl.ClientHandshaker.sendChangeCipherAndFinish(Unknown Source)
at com.sun.net.ssl.internal.ssl.ClientHandshaker.serverHelloDone(Unknown Source)
at com.sun.net.ssl.internal.ssl.ClientHandshaker.processMessage(Unknown Source)
at com.sun.net.ssl.internal.ssl.Handshaker.processLoop(Unknown Source)
at com.sun.net.ssl.internal.ssl.Handshaker.process_record(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readRecord(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.startHandshake(Unknown Source)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.startHandshake(Unknown Source)
at com.mysql.jdbc.ExportControlled.transformSocketToSSLSocket(ExportControlled.java:87)
... 15 more
If I comment out the keystore lines, the connection happens.
//System.setProperty("javax.net.ssl.keyStore","D:/content/dev/connectors/Database (JDBC)/2011.1/src/mykeystore.jks");
//System.setProperty("javax.net.ssl.keyStorePassword","password");,
then the conection happens fine.
My Questions are,
Any idea why I am getting this error with this keystore specified?
I dont want a mutual authentication. Hence I want to say to the server not to validate the client certificate. Is there any property for this?
Any answers are appreciated.
If it works without the keystore and not with it, (a) there is something wrong with what's in it, and (b) you don't need it anyway.
If you don't want to send a client certificate, don't specify a keystore that contains one.
When I test an RMI client and server with the class files it works without any issue on two different machines. Now when I do the same thing with a jar the client fails to connect to the RMIRegistry on the server. Then when I test with the jar on the same machine, the client can connect to the server (even over the network ip and not localhost).
I suspect this has something to do with the RMI registry, but i'm a total novice at RMI, so I have no clue...
I create an RMIRegistry like so:
rmiregistry = LocateRegistry.createRegistry(ServiceConstraints.REGISTRY_PORT);
rmiService = (RmiSubjectService) UnicastRemoteObject.exportObject(this,
ServiceConstraints.REGISTRY_PORT);
rmiregistry.rebind("RmiService", rmiService);
The client connects like this:
remoteService = (RmiSubjectService) Naming.lookup("/" + host + ":"+ port + "/RmiService");
The error I get on the client when running with a jar:
java.rmi.ConnectException: Connection refused to host: 192.168.2.132; nested exception is:
java.net.ConnectException: Connection timed out: connect
at sun.rmi.transport.tcp.TCPEndpoint.newSocket(Unknown Source)
at sun.rmi.transport.tcp.TCPChannel.createConnection(Unknown Source)
at sun.rmi.transport.tcp.TCPChannel.newConnection(Unknown Source)
at sun.rmi.server.UnicastRef.newCall(Unknown Source)
at sun.rmi.registry.RegistryImpl_Stub.lookup(Unknown Source)
at java.rmi.Naming.lookup(Unknown Source)
at ch.uzh.ifi.group10.client.Client.subscribe(Client.java:148)
at ch.uzh.ifi.group10.client.Client.main(Client.java:242)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader.main(JarRsrcLoa
der.java:58)
Caused by: java.net.ConnectException: Connection timed out: connect
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(Unknown Source)
at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at java.net.Socket.<init>(Unknown Source)
at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(Unknown S
ource)
at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(Unknown S
ource)
... 13 more
The problem did turn out to be the network. Specifically it was that I didn't realize that my firewall was blocking the socket, so I could not connect.