Running DAQ Interface » History » Version 59

John Freeman, 11/20/2014 02:34 PM

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h1. Getting help
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If you run into issues, or have questions, please contact:
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* DAQInterface
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** John Freeman -
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* Run Control
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** Erik Blaufuss -
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h1. Starting DAQInterface and Run Control
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DAQInterface is designed to be run, along with rest of the run control code, on, using the lbnedaq account.  These instructions will focus the use of DAQInterface on the gateway node.  If you need access to the account, please contact one of us.
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The DAQInterface and RunControl software can also be run on the lbnedaqtest01 VM machine, please contact John Freeman at, for more details.
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The installed code is located at /data/lbnedaq/scratch/DAQInterface/lbnerc. To get started, login and first setup the environment:
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cd /data/lbnedaq/scratch/DAQInterface
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source fireup
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This will take you into the /data/lbnedaq/scratch/DAQInterface/lbnerc directory. It's a good idea to check whether lbnecontrol (the run control application) and/or DAQInterface (the component which intermediates between run control and artdaq processes) are already running; if they are, the instructions below won't work. To check this, you can try:
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lbnecmd check
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Will display the current state of DAQInterface and RunControl. The example below shows that both RunControl and DAQInterface are running, but the DAQ run is stopped:
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(env)[lbnedaq@lbne35t-gateway01 lbnerc]$ lbnecmd check
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lbnecontrol: running
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daqint@localhost:5770 (synchronous): stopped
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If RunControl is not running, you'll see something like:
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(env)[lbnedaq@lbne35t-gateway01 lbnerc]$ lbnecmd check
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check failed: '[Errno 111] Connection refused'.  Is lbnecontrol running?
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h3. Starting RunControl
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To start RunControl (after loading environment as above):
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lbnecmd launch
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h3. Starting DAQInterface
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To start DAQInterface (after loading environment as above):
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stdbuf -oL daqinterface -n daqint -r 5570 -c localhost -H localhost >>~/DI.log 2>&1 &
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This will launch daqinterface in the background, with all messages being collected (appended to the bottom of...) in the file ~/DI.log  (The stdbuf -oL prevents and buffering of output to the file)
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Here, the "daqint" argument is arbitrary, and is the name you'll give the DAQInterface process in RunControl; the "5570" argument is the port off of which DAQInterface will run. 
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h3. Performing a hard reset of RunControl and DAQInterface
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If needed, you can track down the process names and kill them explicitly to get a clean reset:
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ps aux | grep -v grep | grep lbnecontrol
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ps aux | grep -v grep | grep daqinterface
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If these processes are running, it either means that someone else is using DAQInterface, or that someone else who's done with DAQInterface forgot to clean up. As the 9th and 10th fields of the row of variables "ps aux" returns concern how long the program has been running, you can use these values as well as your best judgement, then, before deciding these processes are not in active use and killing them.   To kill them, the second field returned from "ps aux" is the process id (PID), use:
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kill <PID>
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h1. Configuring and starting Runs
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All of these steps assume that the CfgMgr process is available.  To start this, please see the documentation here:
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Now, you can take DAQ Interface through the standard transitions to start a DAQ run.  At all stages, you can use the "lbnecmd check" command to see what state DAQInterface is in; note that you'll want to wait for a transition to complete before issuing another one, otherwise you'll receive a warning and the transition request will be ignored. DAQInterface will also report to it's log file when transitions are complete:
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Initialize transition complete; if running DAQInterface in the background, can press <enter> to return to shell prompt
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Note that if a high "debug level" has been set, this message can get buried in a set of output messages; in this case "lbnecmd check" may be the easiest way to determine what state the system is in. 
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h2.  Selecting a configuration and DAQcomponents
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*Before initializing or starting a DAQ run*, a configuration and set of DAQComponents must be selected.  This is done via RunControl.
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h3. List and select a configuration:
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To see the list of available configurations (queried from CfgMgr):
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lbnecmd listconfigs
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Will return a list of configs:
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Available configs (Name : description)
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demo : Pithy description
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tmp1 : Pithy description
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Current selected config: No Config
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This lists all available configs, as well as the current selected config (Note, default config is "No Config").  You can then select a configuration:
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lbnecmd setconfig demo
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This will return "OK" if successful (at "listconfigs" will show this as the current config).  If the specified configuration is not known, an error is returned.
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h3. List and select DAQ components.
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You can select which portions of the LBNE DAQ setup you want to use in the upcoming run.  These are mapped generally to the ArtDAQ Boardreader processes
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that read them out.   As an operator, you need to ensure that there are configuration files available in CfgMgr for the DAQ Components that you select here,
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or DAQInterface will return an error.
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To see the list of available DAQ components:
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lbnecmd listdaqcomps
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Will return a list of components available and selected (*Default* is ALL available components):
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{'available': {'component02': ['lbnedaq2', '5206'], 'component01': ['lbnedaq2', '5205']}}
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{'selected': {'component02': ['lbnedaq2', '5206'], 'component01': ['lbnedaq2', '5205']}}
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Shown are the available components by name, along with the requested host/port to run the BoardReader process on. You can then select a list of DAQ components to use in the run:
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lbnecmd setdaqcomps component01 component02
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This will return "OK" if successful (at "lisdaqcomps" will show this as the current config).  If the specified compnents are not known, an error is returned.
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To change the list of available components, see below.
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h2. Configuring, starting, stopping and terminating a Run
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For each of these transitions, please recall that while "lbnecmd <cmd>" returns very quickly, the actual command can take several seconds or minutes to happen.  Before issuing another command, be sure that the transition is complete by using the check command:
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lbnecmd check
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and ensure that the DAQ is, for example, in the "ready" state and not still in the "initializing" stage.
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First, take DAQInterface from the "stopped" to the "ready" state; this will create the artdaq processes on the hosts you selected (DAQ components), and initialize them with the FHiCL configuration:
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lbnecmd init daq
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Take DAQInterface from the "ready" to the "running" state, in order to begin taking data:
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lbnecmd start daq
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Note: the current run number is displayed when DAQ is in the running state using the "lbnecmd check" command:
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lbnecmd check
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lbnecontrol: running
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Run number: 207
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Run configuration: demo
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daqint@localhost:5570 (synchronous): running
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Pause the running of the DAQ, putting DAQInterface into the "paused" state.  This will cause the current open output file to be closed and given a name reflecting the current run number:
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lbnecmd pause daq
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Resume the running of the DAQ, putting returning to the "running" state.  This will restart data taking to a new output file:
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lbnecmd resume daq
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Halt the running of the DAQ, returning DAQInterface to the "ready" state from the "running" state:
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lbnecmd stop daq
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From the ready state, you can start a new run with the same configuration and DAQ components you originally selected. 
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*NOTE* To select a new configuration or DAQ component set, you must kill all ArtDAQ processes with the "terminate" command:
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Now, return to the "stopped" state, killing all the artdaq processes:
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lbnecmd terminate daq
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h2. After your DAQ run.
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Once you've completed your run, there are a few things you can look at. 
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* A record of the DAQ's output will be saved in the subdirectory pmt/ relative to where you specified the output logfiles; thus in the example config.txt below, you'd find the output in /data/lbnedaq/daqlogs/pmt/. 
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* Also, a record of the FHiCL documents sent to the artdaq processes and the docs/config.txt file will have been saved; as of this writing (11/12/14) the directory in which this can be found defaults to /data/lbnedaq/scratch/jcfree/TemporarySaveArea/<run number>, although as you might imagine the plan is to eventually change this directory. 
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** PLEASE NOTE that there may be slight differences between the saved FHiCL documents and the FHiCL documents specified in config.txt and/or provided by the choice of configuration. The saved FHiCL document name is standardized to <processtype>_<host>_<port>_r<run number>.fcl, so, e.g, "Aggregator_lbnedaq2_5266_r192.fcl" would be the saved name of /data/lbnedaq/fcl/Aggregator_lbnedaq2_2.fcl, listed in the example config.txt file above, assuming datataking was performed in run 192. 
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** More importantly, the FHiCL document actually sent to the artdaq process may be slightly different than the FHiCL document provided for DAQInterface; this is because DAQInterface performs some bookkeeping on FHiCL variables which account for things such as the number of processes of a given type (note that it makes no changes which would affect the physics). It is this post-bookkeeping FHiCL document which actually gets sent to the processes which gets saved to the output directory. 
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* Output of the Art modules. Various Art modules may create various types of output. In particular, it's standard for one of the two AggregatorMains running in an artdaq-based DAQ to use Art's RootOutput module, which will save the assembled raw event in an Art-readable *.root file. The location of this output can be found in the FHiCL code used to control RootOutput. The other AggregatorMain typically will run other RootOutput modules designed to create plots, diagnostic printouts, etc.; the nature of the output here is too varied to neatly summarize, but checking the FHiCL code used to control these Art modules should reveal their output location.
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h1. Configuring DAQInterface
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DAQInterface has some key information stored in a local configuration file (location and ports for EventBuilders, Aggregators, location of artDAQ, log level, etc). These can be changed while DAQInterface is not running,  It's expected that for normal operations, these should not need to changed too often. Assuming the processes aren't running, before getting started, take a look at the configuration file, found in docs/config.txt (relative to /data/lbnedaq/scratch/DAQInterface/lbnerc). 
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It should look something like the following:
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lbne-artdaq: /data/lbnedaq/scratch/DAQInterface/build_lbne-artdaq
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PMT host: lbnedaq3
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pause before initialization: 5
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# debug level can range from 0 to 3 (increasing order of verbosity)
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debug level: 1
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log directory:   /data/lbnedaq/daqlogs
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record directory: /data/lbnedaq/scratch/jcfree/TemporarySaveArea/
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 EventBuilder host: lbnedaq2
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 EventBuilder port: 5235
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 EventBuilder fhicl: /data/lbnedaq/fcl/EventBuilder_demo1.fcl
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 EventBuilder host: lbnedaq2
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 EventBuilder port: 5236
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 EventBuilder fhicl: /data/lbnedaq/fcl/EventBuilder_demo2.fcl
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 Aggregator host: lbnedaq2
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 Aggregator port: 5265
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 Aggregator host: lbnedaq2
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 Aggregator port: 5266
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The "lbne-artdaq" parameter allows the user to set the directory in which the desired build of lbne-artdaq to use is located, the "PMT host" parameter is the host on which artdaq's process management tool script (pmt.rb, used by DAQInterface to launch and kill the artdaq processes) will run, and "log directory" is the directory to which lbne-artdaq's output will be sent. The "debug level" parameter allows the user to set the verbosity level of the output to the screen; setting it to higher values creates greater verbosity, and as a practical matter, the range of settings is currently 0-3. Loosely speaking, "0" means minimal output (not much beyond simply announcing a transition is complete), "1" includes announcements of progress during transitions, "2" includes these announcements plus the values of certain variables as well as lbne-artdaq output, and "3" is primarily of developer interest. The "pause before initialization" parameter allows the user to set a pause, in seconds, between when the artdaq processes start and when they're initialized; it has been observed that a latency of a few seconds is needed for initialization to proceed correctly (though this is not always the case -- on lbne35t-gateway01, with a high setting for "debug level", a pause is not needed; the reason why "debug level" matters in this context is not yet understood).
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After these individual parameters, one defines the EventBuilderMain and AggregatorMain artdaq processes. Specifically, an EventBuilderMain is defined in three lines, where each line should contain "EventBuilder", and define the host and port on which the EventBuilderMain will run (to run an artdaq process on the same host as you're on, use "localhost") as well as the FHiCL document used to initialize the EventBuilderMain. AggregatorMain is defined similarly, using the token "Aggregator", but without the FHiCL document supplied, as this is supplied by the choice of configuration in the configuration manager. Best practice is to place the EventBuilderMain's FHiCL documents in the /data/lbnedaq/fcl directory. Please note that the order of processes matters, and that they should be listed front-end to back-end, i.e., EventBuilders should appear before Aggregators.
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h1. Adding new configurations to RunControl
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Adding a new configuration selectable from RunControl is quite simple. As of 11/20/14, the FHiCL documents associated with a given configuration are stored within the directory
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where "named_configuration" would be the name of the configuration, in this example. Within this directory, the following files are expected:
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* Aggregator1.fcl and Aggregator2.fcl, used to initialize the two AggregatorMain processes in the DAQ system
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* <named_component>_hw_cfg.fcl, used to initialize the BoardReaderMain process running the fragment generator associated with detector component "named_component". Note that there can be any number of such files associated with a configuration, as long as a given component is registered to RunControl (see below, "Adding new DAQ Components to RunControl")
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There are existing examples of configurations currently within /data/lbnedaq/config which can be studied (and even copied) for further guidance; however, please disregard the "tmp1" and "tmp2" configurations. Note that the FHiCL documents in these directories contain some variables which are set to "PLACEHOLDER", e.g.
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 event_builder_count: PLACEHOLDER
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Note that this is not legal FHiCL, but that DAQInterface will substitute in the appropriate value before using the FHiCL document to initialize an artdaq process; here, for example, it would replace "PLACEHOLDER" with the actual number of EventBuilderMain processes being run. 
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h1. Adding new DAQ Components to RunControl
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The list of available DAQComponents (maps to BoardReader processes) is maintained by RunControl in the file:
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Each entry (name: host port) defines:
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* name - name of the component, maps to a <name>_hw_cfg.fcl in CfgMgr's configuration directory
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* host - hostname where BoardReader process will be started
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* port - XMLRPC port to be used, must be unique and used by other processes.
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For example:
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component01: lbnedaq2 5205
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component02: lbnedaq2 5206
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Has two components (component01 and component02) both running on lbnedaq2 on ports 5205 and 5206.
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h1.  Troubleshooting and FAQ
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h2.  Common RunControl issues
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h3. How can I get a list of all RunControl commands?
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lbnecmd help
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will list all available commands for RunControl with some details for help.  
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h3.  No real configurations are listed by RunControl
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If you run "lbnecmd listconfigs" and see something like:
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Available configs (Name : description)
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dummy : Dummy description
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Instead of your expected configurations, RunControl is not able to connect to CfgMgr.  Please make sure it's running (
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h2.  Common DAQInterface issues
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h3.  *Error handling*
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As of this writing (11/14/14) certain potential problems have been anticipated and are handled within DAQInterface. These problems include:
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# An artdaq process returns an error state after a transition request, or an exception is thrown by the XML-RPC library during the request
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# During periodic checks, one or more artdaq processes expected to exist are not found
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In either case, an error is reported via 0MQ to RunControl, and the "Recover" transition is automatically triggered. This transition is a fairly blunt instrument: it will kill any remaining artdaq processes and return DAQInterface to its original state of "stopped" (i.e., one in which it requires the "init" transition before anything else is done). 
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h3. *Your change to docs/config.txt or doesn't seem to do anything*
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Make sure you kill the existing daqinterface process and restart it
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h3. *On the initial transition ("lbnecmd init daq"), you see "error: [Errno 111] Connection refused"*
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If a "Recover" is triggered and you can see via "lbnecmd check" that DAQInterface is in the "stopped" state, try initializing again. If that doesn't work, you can try increasing the value of the "pause before initialization" variable in the docs/config.txt file. Empirically, it appears there needs to be a pause of at least 4 seconds on before the FHiCL documents can be successfully sent via XML-RPC to the processes; increasing this value may make it less likely that the "Connection refused" error occurs.
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h3. *On the initial transition, you see a regularly updating printout saying "Waiting for all processes to be launched"*
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Seeing one or two of these is fine. If, after several seconds, something like the following
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Waiting for all processes to be launched; if zombie pmt.rb is running on localhost please kill it and this program (PID 31820)
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keeps getting output to screen, it means there's a problem initializing. In this case, the current (11/12/14) course of action is to externally kill DAQInterface using the PID listed; also, it's possible that there may already be a pmt.rb executable running on the desired host, blocking the launch of a new one due to a port conflict, in which case you should log onto the host (assuming you're not already on it), and run 
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ps aux | grep -v grep | grep pmt.rb 
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to see if this is the case. If it's not and you can't think of what might be wrong (is the configuration manager running? have you double-checked docs/config.txt?), then try increasing the debug level in docs/config.txt for your next run-through, as this will likely shed light on the nature of the problem.