Develop Reference

IBM MQ 8 to 9 Migration

We have Sprintboot application on Azure Linux VM which is connecting to IBM MQ 8 and connection goes via KPN.
Recently we have upgraded IBM MQ from 8 to 9. No settings are changed on application, but with IBM MQ 9 - we can see that post 30 mins - connections are getting timed out and new connections are getting created post every 30 mins.
Checked with IBM MQ 9 team - no timeout setting at their end.
Error -
[com.ibm.mq.allclient-9.2.3.0.jar!/:9.2.3.0 - p923-L210708]
Caused by: com.ibm.mq.jmqi.JmqiException: CC=2;RC=2009;AMQ9208: Error on receive from host 'Host Details'. [1=javax.net.ssl.SSLException[Connection timed out (Read failed)],3=,4=TCP,5=InputStream.read]
Caused by: javax.net.ssl.SSLException: Connection timed out (Read failed)
Suppressed: java.net.SocketException: Broken pipe (Write failed)
enter code here`Caused by: java.net.SocketException: Connection timed out (Read failed)

What JSchExceptions are thrown when connection timeout occurs and when file transfer using put is interrupted?

I am trying to add retry mechanism to my SFTP client which uses JSch. I want to retry sending the file in the following scenarios:
Connection timeout occurs
File transfer to remote host using put is interrupted, because of connection issues
What specific JSchException messages should I check?
These are the few exceptions I came across (I am not aware of the difference):
com.jcraft.jsch.JSchException: timeout: socket is not established
com.jcraft.jsch.JSchException: Session.connect: java.net.SocketTimeoutException: Read timed out

JMS - Couldn't create session factory even if connection to remote provider is OK

I make a jar to connect to JMS provider, it's work fine in a server (a) but doesn't work on a server (b).
I verify that connection to the JMS provider from server (b) is OK via telnet as shown below:
-> telnet -d 10.127.161.247 4447
Trying 10.127.161.247...
Connected to 10.127.161.247.
The logs and exception that it's throw is below :
2018/08/01 11:19:47:921 - Processing command line arguments...
2018/08/01 11:19:47:927 - Preparing the output... Writing to file = true
2018/08/01 11:19:50:315 - Trying to establish connection, attempt: 0
2018/08/01 11:19:52:132 - Connecting to provider: remote://10.127.161.247:4447 using user: oad_user
2018/08/01 11:19:52:132 - Creating a regular (non-secure) connection factory...
2018/08/01 11:19:53:073 - Opening a connection to the JMS provider...
2018/08/01 11:20:24:192 - Attempt failed: Failed to create session factory
javax.jms.JMSException: Failed to create session factory
at org.apache.activemq.artemis.jms.client.ActiveMQConnectionFactory.createConnectionInternal(ActiveMQConnectionFactory.java:675)
at org.apache.activemq.artemis.jms.client.ActiveMQConnectionFactory.createTopicConnection(ActiveMQConnectionFactory.java:267)
at com.alcatel.ossgw.client.jms.JmsSubscriberClient.prepareConnection(JmsSubscriberClient.java:334)
at com.alcatel.ossgw.client.jms.JmsSubscriberClient.connect(JmsSubscriberClient.java:274)
at com.alcatel.ossgw.client.jms.JmsSubscriberClient.listen(JmsSubscriberClient.java:97)
at com.alcatel.ossgw.client.jms.JmsSubscriberClient.main(JmsSubscriberClient.java:536)
Caused by: ActiveMQNotConnectedException[errorType=NOT_CONNECTED message=AMQ119007: Cannot connect to server(s). Tried with all available servers.]
at org.apache.activemq.artemis.core.client.impl.ServerLocatorImpl.createSessionFactory(ServerLocatorImpl.java:818)
at org.apache.activemq.artemis.jms.client.ActiveMQConnectionFactory.createConnectionInternal(ActiveMQConnectionFactory.java:67
I don't how to debug such a problem knowing i'm new in JMS, i'll be grateful for any remarks and ideas..
Many thanks

Did you ever find out why this was happening?
I have a related issue where an active JMS connection suddenly disconnects and the system starts throwing this exception until a system restart is done and then it connects again without fail.

Storm - java.net.ConnectException: Connection refused

I have deployed storm server, but I am receiving the following error every time I start supervisor.
2014-09-08 09:04:40 o.a.z.ClientCnxn [INFO] Opening socket connection to server localhost/127.0.0.1:2181. Will not attempt to authenticate using SASL (unknown error)
2014-09-08 09:04:40 o.a.z.ClientCnxn [WARN] Session 0x0 for server null, unexpected error, closing socket connection and attempting reconnect
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method) ~[na:1.7.0_65]
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:739) ~[na:1.7.0_65]
at org.apache.zookeeper.ClientCnxnSocketNIO.doTransport(ClientCnxnSocketNIO.java:350) ~[zookeeper-3.4.5.jar:3.4.5-1392090]
at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1068) ~[zookeeper-3.4.5.jar:3.4.5-1392090]
can anyone please help me with the error.
Thanks in advance

Starting Zookeeper was my issue here:
zkServer start
After which you should rerun the topology.

Have you setup Zookeeper? Zookeeper should be up and running before running storm topologies.
In the storm documentation refer to Set up a Zookeeper cluster section.

This exception has one meaning only: nothing was listening at the IP:port you tried to connect to. Either that was wrong or you didn't start the server.

Go to Zookeeper Installation directory.
cd to bin.
Give the command ./zkServer stop in all zookeeper nodes.
Again give the command ./zkServer start in all zookeeper nodes.
Start all the storm processes(Nimbus and Supervisor).
Now you will not get this exception in Zookeeper cluster.

Unable to connect to ftp server java

I should be able to successfully send and receive file to/from FTP server.
But then, no changes occurred in the code and I started getting this :
Error: java.net.ConnectException: Connection timed out: connect
What I am doing is:
FTPClient ftp = new FTPClient();
ftp.connect( IPADDRESS of FTP server);
connect() is giving this execption. I am not understanding the cause for it.

The error message is telling you that the OS's attempt to connect to the server timed out. This typically means that:
the remote server has dropped off the network, or
something (e.g. a firewall) is "black holing" packets sent to the server on the FTP port.

Signals that an error occurred while attempting to connect a socket to a remote address and port. Typically, the connection was refused remotely (e.g., no process is listening on the remote address/port).
Source: JavaDoc.