Error 81015 when logging into DataStage

Unable to connect to host error 81015 when logging into IBM InfoSphere DataStage (DS):

Failed to connect to host: <hostname>, project: UV 
(The connection has timed out (81015)) 

• The error usually indicates that either the port that the client is using (e.g.,31538) is blocked by a firewall or the permissions on file system for the DS installation has changed.
  
  Try the following command:
  
  telnet <hostname> <port>
  
  Please check with your network administrator to confirm that the DataStage port is not being blocked or being used by another application.
  
• The inactivity time out in DS Administrator is set to "Do not timeout"
  
  The inactivity timeout parameter depends on the usage in your environment. There is no recommended value. It is important to ensure that all the developers can work without incurring in the inactivity timeout while they are developing, but it is also important that the developers do not leave open jobs in editing mode for too long when the session times out, otherwise that will lock the jobs and possibly corrupt the repository.
  
  It is recommended to set the inactivity timeout value to some value.
  
• Perform a clean shutdown/startup of DataStage engine:
  1. Log on to server as dsadm or root
     
  2. Make sure that no one is using DataStage.
     
  3. Check if there are any processes left
     
     ps -ef | grep phantom
     ps -ef | grep dsapi_slave
     ps -ef | grep dscs
     
     These commands should not return any results. If they return results, it means that there are still some processes. You can wait for the users to stop their processes or kill the processes (using kill -9 PID).
     
  4. Check datastage shared memory segments:
     
     ipcs - mop | grep ade
     
     If there any shared memory segments returned, remove them, use command:
     
     ipcrm -m ID , where ID is the number from the second column of ipcs -mop
     
  5. Check if dsrpc is running:
     
     netstat -a | grep dsrpc
     
     If dsrpc is running then you should get a line with the status LISTEN. If you get more lines it means that there are still some connections and you need to wait. If you see that dsrpc or other connections are in status WAIT then you also need to wait until this it disappears (you can also reboot the machine)
     
  6. cd to $DSHOME
     
  7. Source the dsenv:
     
     . ./dsenv (that is dot space dot forward-slash dsenv)
     
  8. At this point you can stop or start the DS Engine.
     
     ./bin/uv -admin -stop
     ./bin/uv -admin -start
• If you are using an Active/Passive high availability environment, ensure that your environment is configured so that the virtual host id is directed to the currently active machine, otherwise requests sent to the inactive/passive machine may fail with error 81015.