NOvA » NOvA Data Driven Trigger

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h1. NDOS Shifter Instructions

h2. Starting the Trigger

*The following steps show how to start the trigger processes on the buffer nodes.  As long as the buffer nodes are up, you can execute these instructions, but it is usually done shortly before you begin the run.*

*1. The DDTManager should be in the list of managers of the DAQApplicationManager:*

!ddt_daqapplicationmanager.png!

*2. Just before you start the run, you should see the DDT Manager with several buttons in pink:*

!ddtmanager_allstopped.png!

*3. Click the "Start Group" button to start all of the processes and when they are all running it should look like this:*

!ddtmanager_allrunning.png!

*Note that the data-driven triggers record shorter time windows, so you will see very clean events in the Event Display.*

h2. Stopping the Trigger

*1. Click the "Stop Group" button and wait until everything is pink (not running).  Make sure that you stop all of the processes before you end a run or after a run crashed!*

!ddtmanager_allstopped.png!

h2. Recovering a Trigger

*Occasionally a trigger process might die, so you can recover it as follows:*

*1. The overview will indicate this with a bit of pink in the Group button (Group 05 here), so double-click it to see more details:*

!ddtmanager_onestopped_overview.png!

*2. Send an email to novaddt@fnal.gov telling us which trigger process died.  For example, trigger process DDT-6-4 died here:*

!ddtmanager_onestopped.png!

*3. Right-click on the dead process and click "Start Process":*

!ddtmanager_restart.png!

*4. Everything should be green again.  You can return to the Overview by clicking on the orange "Back" button.*

!ddtmanager_allrunningagain.png!

*5. If the process dies more than twice in an hour, do not restart it again, but notify us via email.*