Hall C CODA/DAQ Layout

Hall C CODA Layout

• Detailed 'User' instructions are on the Hall C DAQ page. That includes the ROC layout, standard recovery procedures, etc. Read and understand that first.
  • Includes instructions on updating F250 pedestals, switching DAQ modes, recovery procedures, etc.

CODA process and file locations

See also: Hall C Compute Cluster

The primary host for the "coinc" config is cdaql6

• "coinc" or "NPS" run on coda@cdaql6.
• HMS-standalone: coda@cdaql5
• SHMS DAQ is disabled at the moment.

When running in 'coincidence' mode, all ROCs (NPS+HMS) are picked up.

There is nothing 'special' about those machines however. If needed, failover to another host by replacing 'cdaql6' with a new/different host in

• coda:bin/coda_user_setup
• coda:bin/run-vncserver -- This will start a new CODA VNC server session (should only be run on cdaql5 or cdaql6). This will run @reboot via crontab
• BTW, we don't use msqld anymore, it was for the older version of CODA.

CODA support software

• The start-/end-of-run scripts, EPICS logger scripts, RunStart GUI, Prescale GUI are located in coda:coda/scripts/
• There are multiple 'README' files in that directory and its children that describe the intended execution flow and `best practices'
• Log files in coda:debug_logs/ may be useful in understanding problems.
• CODA support files detailed notes

ROC code

• Only the experts should be changing the ROC code.

Experiment Changeover Tasks

This is probably a little obsolete but I'll leave it for now (noted Aug 2023).

• Ensure all CODA files from prior run are pushed to the old tape destination and removed from the data/raw/ directory
  • Move any 'orphan' files from ~coda/data/raw/
  • Run jmirror-sync-raw.copiedtotape push as coda@cdaql1
    • Note that files will only be removed from the local system by jmirror if both the original copy and duplicate copy are on tape. Either repeat the jmirror-sync-raw.copiedtotape push command after the tape system has made the duplicates, or wait and the cron job will clear things up for you within a few days.
• Update the '~coda/coda/scripts/DATAFILE-Locations.sh' to point at the new 'raw/' tape destination
  • NOTE: Only do this after all prior files have been moved or you can get files mixed up on tape.
  • This file is used by CODA and the data mover scripts to move raw CODA files at end of run (and watch for and correct file transfer interruptions, etc)
• Update the 'T1, T2, ... T6' cables into the Trigger Master(s) modules to match Experimental requirements.
  • Note: The EDTM system is designed to trigger all detector pretriggers (3/4, PbGl, Cerenkovs, etc) with timing similar to what the physics will generate (including SHMS+HMS coincidences) so that can get you quite close pre-beam. However, the timing will need to be checked/tweaked when beam arrives (of course).
• Confirm the trigger table mapping is consistent with the Experimental requirements.
  • This table sets the 'trigger bits' that the Trigger Master adds to its data header to flag whether an particular trigger involved the SHMS, HMS, etc.

• Update the target ladder list in '~coda/coda/scripts/runstart_gui.tcl' to match actual target ladder (allows the prescale GUI to auto select the in-use target).

• Trigger timing log entries / snapshots are in the logbook and are also recorded here: Trigger History
• Ensure the go_analysis script is updated and pointing at the right replay scripts.
  • Update the cdaq:hallc-online/ symlink to point at the new experiment directory
  • Ensure symlinks in the new experiment directory are pointing at the right Hall C cluster /net/cdaq/cdaqlXdata/cdaq/<experiment> directories and are not writing files into the /home/cdaq/ directory.

Data Movers

The 'data mover' algorithm takes care of copying CODA data files from the Hall C system(s) to tape. Please don't interfere with this.

The mover relies on jmirror.

Clean-up of the local files is managed by the 'jmirror' tool.

There are crontab entries under coda@cdaql5 that monitor the file transfers for 'stuck' files or other issues and will email responsible parties.

Git repos

All of the CODA configurations, coda:bin/, and other directories are maintained with git.

The remote repos are stored on the 'hallcgit.jlab.org' server.