Reverting to the previous maintenance level on Linux

You can remove updates and revert to the previous maintenance level of IBM® MQ by using RPM. The same procedure applies to all Linux® platforms, including Ubuntu.

1. Log in as a user in group mqm.
2. Stop all applications using the IBM MQ installation.

   If you use the Managed File Transfer (MFT) component, ensure that any MFT agents have finished all of the file transfers that they were engaged in. There should be no incomplete transfers associated with the agents, and their SYSTEM.FTE.STATE queues should contain no messages.

3. End all the activity of queue managers associated with the IBM MQ installation.
   1. Run the dspmq command to list the state of all the queue managers on the system.

      Run either of the following commands from the installation that you are updating:

      
      dspmq -o installation -o status
      dspmq -a
      

      dspmq -o installation -o status displays the installation name and status of queue managers associated with all installations of IBM MQ.

      dspmq -a displays the status of active queue managers associated with the installation from which the command is run.

   2. Use the MQSC command DISPLAY LSSTATUS to list the status of listeners associated with a queue manager, as shown in the following example:

      
      echo "DISPLAY LSSTATUS(*) STATUS" | runmqsc QmgrName
      

   3. Run the endmqm command to stop each running queue manager associated with this installation.
      

      The endmqm command informs an application that the queue manager it is connected to is stopping; see Stopping a queue manager.

      For the maintenance to proceed, applications must respond to an endmqm command by disconnecting from the queue manager and releasing any IBM MQ libraries they have loaded. If they do not, you must find another way to force applications to release IBM MQ resources, such as by stopping the applications.

      You must also stop applications that are using the client libraries that are part of the installation. Client applications might be connected to a different queue manager, running a different installation of IBM MQ. The application is not informed about queue managers in the current installation being shut down.

      Any applications that continue to have IBM MQ shared libraries from the installation loaded prevent you applying IBM MQ maintenance. An application might disconnect from a queue manager, or be forcibly disconnected, but keep an IBM MQ shared library loaded.

      Note: Applying maintenance level updates to multi-instance queue managers on Linux describes how to apply maintenance to a multi-instance queue manager. A multi-instance queue manager can continue to run on one server, while maintenance is applied to another server.
   4. Stop any listeners associated with the queue managers, using the command:

      
      endmqlsr -m QMgrName
      

4. Log in as root, or with sufficient authority to run the following commands.

   You can do this by adding sudo before the commands, or by changing to the root user in the shell with the su command. For more information, see Exploring the differences between sudo and su commands in Linux.

5. Run the rpm command to find out which packages are installed on your server.

   Enter the following command:

   
   rpm -qa | grep MQSeries
   

   Note: If you are using Ubuntu, add the --force-debian attribute.

   
   rpm --force-debian -qa | grep MQSeries
   

   Using the example given in Applying maintenance level updates on Linux using RPM, returns:

   
   MQSeriesRuntime-V.R.0-0
   MQSeriesSDK-V.R.0-0
   MQSeriesServer-V.R.0-0
   MQSeriesRuntime-Uxxxx-V.R.0-1
   MQSeriesSDK-Uxxxx-V.R.0-1
   MQSeriesServer-Uxxxx-V.R.0-1
   

   where V is the version number and R is the number of the Release.
   Note: If you are using the RDQM facility you might need to use a different process to revert to a prior level.

   See Installing RDQM (replicated data queue managers) for more information.

6. Run the rpm command to remove all the updates applied at level 1.

   Enter the following commands:

   
   rpm -ev MQSeriesRuntime-Uxxxx-V.R.0-1 MQSeriesSDK-Uxxxx-V.R.0-1
   MQSeriesServer-Uxxxx-V.R.0-1
   

   where V is the version number and R is the number of the Release.
7. Repeat step 5 to check that the ptf packages have been removed, leaving only the original installation packages:

   
   MQSeriesRuntime-V.R.0-0
   MQSeriesSDK-V.R.0-0
   MQSeriesServer-V.R.0-0
   

   where V is the version number and R is the number of the Release.