1.JAVA_HOME is set to IBM JAVA SDK.
2.Unable to get oracle database connection. Where as tried running the same on machine having Oracle java set as JAVA_HOME
3.Placed ojdbc14.jar under AppServer/lib.
try {
connection = DriverManager.getConnection(
"jdbc:oracle:thin:#[server-ip]:[server-port]/[dbname]", "[uname]", "[pass]");
} 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!");
}
Is there any setting i need to do.Below is the error
Oracle JDBC Driver Registered! Connection Failed! Check output console
java.sql.SQLRecoverableException: IO Error: The Network Adapter could
not establish the connection
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:517)
at oracle.jdbc.driver.PhysicalConnection.(PhysicalConnection.java:557)
at oracle.jdbc.driver.T4CConnection.(T4CConnection.java:233)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:29)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:556)
at java.sql.DriverManager.getConnection(DriverManager.java:583)
at java.sql.DriverManager.getConnection(DriverManager.java:227)
at OracleJDBCExample.main(OracleJDBCExample.java:29) Caused by: oracle.net.ns.NetException: The Network Adapter could not
establish the connection
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:389)
at oracle.net.resolver.AddrResolution.resolveAndExecute(AddrResolution.java:431)
at oracle.net.ns.NSProtocol.establishConnection(NSProtocol.java:882)
at oracle.net.ns.NSProtocol.connect(NSProtocol.java:267)
at oracle.jdbc.driver.T4CConnection.connect(T4CConnection.java:1625)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:365)
... 7 more Caused by: java.net.SocketTimeoutException: connect timed out
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:370)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:231)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:213)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:404)
at java.net.Socket.connect(Socket.java:643)
at oracle.net.nt.TcpNTAdapter.connect(TcpNTAdapter.java:147)
at oracle.net.nt.ConnOption.connect(ConnOption.java:130)
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:367)
Thanks,
Kusuma
Here's a couple of things to check:
can you connect to port [server-port] on [server-ip] ? (try telnet, netcat or something similar)
does the listener accept connections? i.e. does sqlplus username/pw#[server-ip]:[server-port]/[dbname] work?
is the SID correct (dbname) ?
have you tried connecting with the service name instead of the SID:
jdbc:oracle:thin:#//<server-ip>:<server-port>/<dbname> ?
see also
Java JDBC - How to connect to Oracle using Service Name instead of SID
Related
We are using REDIS cache , and using Spring-Redis module , we set the maxActiveConnections 10 in application configuration , but sometimes in my applications am seeing below errors
Exception occurred while querying cache : org.springframework.data.redis.RedisConnectionFailureException: Cannot get Jedis connection; nested exception is redis.clients.jedis.exceptions.JedisConnectionException: Could not get a resource from the pool
is it because of in the Redis server their are no more connections to give to my applications or any other reason , can anyone please suggest on this ?
Note : their are 15 applications which are using the same Redis server to store the data , i mean 15 applications need connections from this single redis server only , for now we set 10 as maxActiveConnections for each of the 15 applications
To check how many clients are connected to redis you can use redis-cli and type this command: redis> INFO more specifically info Clients command.
192.168.8.176:8023> info Clients
# Clients
connected_clients:1
client_longest_output_list:0
client_biggest_input_buf:0
blocked_clients:0
Form Jedis source code, it seems that the exception happened for the following reason:
Exhausted cache: // The exception was caused by an exhausted pool
or // Otherwise, the exception was caused by the implemented activateObject() or ValidateObject()
Here is the code snippet of Jedis getResource method:
public T getResource() {
try {
return internalPool.borrowObject();
} catch (NoSuchElementException nse) {
if (null == nse.getCause()) { // The exception was caused by an exhausted pool
throw new JedisExhaustedPoolException(
"Could not get a resource since the pool is exhausted", nse);
}
// Otherwise, the exception was caused by the implemented activateObject() or ValidateObject()
throw new JedisException("Could not get a resource from the pool", nse);
} catch (Exception e) {
throw new JedisConnectionException("Could not get a resource from the pool", e);
}
}
I am trying to use HBase for building some real time API's. Hence my use case is to support ~10000 concurrent requests per second. I am trying to do some connection pooling so as to achieve multi thread access. I followed this documentation to create the connection: https://hbase.apache.org/1.1/apidocs/org/apache/hadoop/hbase/client/ConnectionFactory.html
But I keep getting this error when I make concurrent requests to my API:
WARN [http-nio-34000-exec-93-SendThread(d-3zjyk02.target.com:2181)]
19 Apr 2017 04:48:13:872 (ClientCnxn.java:1102) - Session 0x0 for
server d-3zjyk02.target.com/10.66.241.30:2181, unexpected error,
closing socket connection and attempting reconnect
java.io.IOException: Connection reset by peer
at sun.nio.ch.FileDispatcherImpl.read0(Native Method)
at sun.nio.ch.SocketDispatcher.read(SocketDispatcher.java:39)
at sun.nio.ch.IOUtil.readIntoNativeBuffer(IOUtil.java:223)
at sun.nio.ch.IOUtil.read(IOUtil.java:192)
at sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:380)
org.apache.zookeeper.ClientCnxnSocketNIO.doIO(ClientCnxnSocketNIO.java:68)
at
org.apache.zookeeper.ClientCnxnSocketNIO.doTransport(ClientCnxnSocketNIO.java:366)
at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1081)
Here is how I am creating the connection:
// Connection to the cluster. A single connection shared by all application threads
private Connection connection = null;
public Connection getHBaseConnection() throws Exception {
if (connection == null) {
try {
Configuration configuration = HBaseConfiguration.create();
configuration.addResource("core-site.xml");
configuration.addResource("hbase-site.xml");
configuration.addResource("hdfs-site.xml");
connection = ConnectionFactory.createConnection(configuration);
} catch (Exception ex) {
LOG.error("Exception in creating the HBase connection object: " + ex.getMessage());
throw new Exception("Exception in creating the HBase connection: " + ex.getMessage());
}
}
return connection;
}
And here is how I use the get HBase connection method to some scan operations:
try {
connection = getHBaseConnection();
afterConnectionStartTime = System.currentTimeMillis();
LOG.info("[" + (System.currentTimeMillis() - startTime) + "]ms" + " ...TIME TAKEN to get the HBase connection object");
if (connection != null) {
table = connection.getTable(TableName.valueOf(TABLE_NAME));
Scan scan = new Scan(Bytes.toBytes(rowKeyStartDate), Bytes.toBytes(rowKeyEndDate));
scan.addColumn(COLUMN_FAMILY, ITEM);
}
This code works fine for any number of sequential requests, but when I do concurrent requests, I keep getting this error.
Some of the observations from my research on this issue:
1) This error is related to zookeeper closing the socket after certain number of requests (which I assume when it exceeds the max client connections (40) mentioned in my zoo.cfg file). But what I don't understand is why the concurrent requests are going to zookeeper in the first place. The first request should open the connection object and all the subsequent requests should use that pre existing connection to directly talk to region servers.
2) I am assuming this is the right way to do the connection pooling (at least as per the official Hbase doc). If no, whats the right way to do it?
3) I don't want to increase the max client connections in the zookeeper cfg file, thought it might be a temporary hack that can do my work.
Any help / suggestions is much appreciated.
Thanks!
Installed the filezilla server and enabled the FTP over TLS Settings in Settings and started the server.
Through eclipse java client i tried to connect to server for upload and download the file using the below code
using commons-net apache library.
FTPSClient ftpClient = new FTPSClient(false);
// Connect to host
ftpClient.connect(mServer, mPort);
int reply = ftpClient.getReplyCode();
System.out.println("The reply code is "+reply);
if (FTPReply.isPositiveCompletion(reply)) {
// Login
if (ftpClient.login("******", "*******")) {
// Set protection buffer size
ftpClient.execPBSZ(0);
// Set data channel protection to private
ftpClient.execPROT("P");
// Enter local passive mode
ftpClient.enterLocalPassiveMode();
// Upload File using storeFile
File firstLocalFile = new File("e:/Test.txt");
String firstRemoteFile = "hello.txt";
InputStream is = new FileInputStream(firstLocalFile);
String result = getStringFromInputStream(is);
System.out.println(result);
Object output = ftpClient.storeFile(firstRemoteFile, is);
System.out.println(output);
is.close();
// Download File using retrieveFile(String, OutputStream)
String remoteFile1 = "/settings.xml";
File downloadFile1 = new File("e:/testOutput.xml");
OutputStream outputStream1 = new BufferedOutputStream(new FileOutputStream(downloadFile1));
boolean success = ftpClient.retrieveFile(remoteFile1, outputStream1);
outputStream1.close();
if (success) {
System.out.println("File #1 has been downloaded successfully.");
}
// Logout
ftpClient.logout();
// Disconnect
ftpClient.disconnect();
} else {
System.out.println("FTP login failed");
}
// Disconnect
ftpClient.disconnect();
} else {
System.out.println("FTP connect to host failed");
}
} catch (IOException ioe) {
System.out.println("FTP client received network error");
ioe.printStackTrace();
} catch (Exception nsae) {
System.out.println("FTP client could not use SSL algorithm");
nsae.printStackTrace();
}
It creates a file hello.txt on the server but size is of 0kb (source file size is 10 kb) and ended up the following error. Please help me to resolve this
javax.net.ssl.SSLHandshakeException: Remote host closed connection during handshake
at sun.security.ssl.SSLSocketImpl.readRecord(Unknown Source)
at sun.security.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source)
at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)
at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)
at org.apache.commons.net.ftp.FTPSClient._openDataConnection_(FTPSClient.java:619)
at org.apache.commons.net.ftp.FTPClient._storeFile(FTPClient.java:633)
at org.apache.commons.net.ftp.FTPClient.__storeFile(FTPClient.java:624)
at org.apache.commons.net.ftp.FTPClient.storeFile(FTPClient.java:1976)
at com.test.ftps.TestClass.main(TestClass.java:88)
Caused by: java.io.EOFException: SSL peer shut down incorrectly
at sun.security.ssl.InputRecord.read(Unknown Source)
... 9 more
just un-tick
"Require TLC session resumption on data connection..." in the filezilla server -> settings -> FTP over TLS Settings -> un-tick the Require TLC session resumption on data connection when using PROT P
In addition to user2750213's answer ( Filezilla's TLS session resumption ) beware to have the required protocols enabled. You can verify them running this code or this other on the jvm connecting to the FTPS server. Recent versions of Filezilla server use TLSv1.2.
If this works for you, you may get a java.net.SocketException: Unconnected sockets not implemented. In this case you need to write your own class which extends DefaultSocketFactory class and then set it to your FTPS client via method ftpsClient.setSocketFactory(yourSocketFactory) overriding the createSocket() method which must returns a new Socket()
I have the below code to SFTP to a location
public static void putFile(String username, String host, String password, String remotefile, String localfile){
JSch jsch = new JSch();
Session session = null;
try {
session = jsch.getSession(username, host, 22);
session.setConfig("StrictHostKeyChecking", "no");
session.setPassword(password);
session.connect();
Channel channel = session.openChannel("sftp");
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
sftpChannel.put(localfile, remotefile);
sftpChannel.exit();
session.disconnect();
} catch (JSchException e) {
e.printStackTrace();
} catch (SftpException e) {
e.printStackTrace();
}
}
I am able to SFTP the document from my local machine using the above code. However when I am trying from a different environment to SFTP to the same location I am getting the follow error.
com.jcraft.jsch.JSchException: invalid server's version string at
com.jcraft.jsch.Session.connect(Session.java:253)
Note : I am using jsch-0.1.31.jar file.
on printing out session.getClientVersion() I am getting "SSH-2.0-JSCH-0.1.31".
I tried to upgrade the jar file to jsch-0.1.51.jar then session.getClientVersion() = "SSH-1.5-JSCH-0.1.51" and I am getting the following error
com.jcraft.jsch.JSchException: Session.connect: java.net.SocketException: Connection reset at com.jcraft.jsch.Session.connect(Session.java:558)
Please can you help me on what parameters should I be looking into and what is causing it to run from my local machine and upload to the same SFTP location and not from other environment?
As noted by #Kenster, the exception is about server's version string, not client's. The "invalid server's version string" exception is thrown by following code in Session.connect:
if(i==buf.buffer.length ||
i<7 || // SSH-1.99 or SSH-2.0
(buf.buffer[4]=='1' && buf.buffer[6]!='9') // SSH-1.5
){
throw new JSchException("invalid server's version string");
}
First, I would try to connect with some client that logs the version string and see yourself. For example with WinSCP, search its log for a pattern like:
. 2014-09-03 17:01:20.596 Server version: SSH-2.0-OpenSSH_5.3
(I'm the author of WinSCP)
Though possibly it's not about version string at all. I would rather believe the error raised by the new version, the Connection reset. The old version may fail to detect that the connection was aborted prematurely and tries to validate some random or incomplete data.
The Connection reset may indicate wide variety of different errors
Server refusing a connection from the other location
Some firewall or proxy not allowing the connection to pass through
I start h2 database in a servlet context listener:
public void contextInitialized(ServletContextEvent sce) {
org.h2.Driver.load();
String apprealPath = sce.getServletContext().getRealPath("\\");
String h2Url = "jdbc:h2:file:" + apprealPath + "DB\\cdb;AUTO_SERVER=true";
LoggerContext lc = (LoggerContext) LoggerFactory.getILoggerFactory();
StatusPrinter.print(lc);
logger.debug("h2 url : " + h2Url);
try {
conn = DriverManager.getConnection(h2Url, "sa", "sa");
} catch (SQLException e) {
e.printStackTrace();
}
logger.debug("h2 database started in embedded mode");
sce.getServletContext().setAttribute("connection", conn);
}
then I try to use dbvisualizer to connect to h2 using following url :
jdbc:h2:tcp://localhost/~/cdb
but get these error messages:
An error occurred while establishing the connection:
Type: org.h2.jdbc.JdbcSQLException Error Code: 90067 SQL State: 90067
Message:
Connection is broken: "Connection refused: connect" [90067-148]
I tried to replace localhost with "172.17.33.181:58524" (I found it in cdb.lock.db)
reconnect with user "sa" password "sa" ,then server response changed to :
wrong username or password !
In the Automatic Mixed Mode, you don't need to (and you can't) use jdbc:h2:tcp://localhost. Just use the same URL everywhere, that means jdbc:h2:file:...DB\\cdb;AUTO_SERVER=true.
You can use the same database URL independent of whether the database is already open or not. Explicit client/server connections (using jdbc:h2:tcp:// or ssl://) are not supported.