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QClog Daemon


QClog is application based on the SeisComP3 framework that receives QC messages and stores all station parameters in a Round Robin Database(RRD). The stored station parameters can be visualized in a user friendly way using the integrated web front-end. The front-end provides three differrent views: The admin, the overview and the station page. The first one controls the style of GUI. The second page gives an overview of all stations received QC messages for. Here the user can see at a glance which stations are delayed. The latter one is a detail view that shows delay, latency, offset and other QC parameter of a station. Besides the different QC parameter the data is plotted in a graph.


  • rrdtool 1.4.2 or higher
  • Apache HTTP Server
  • mod_python - Apache/Python Integration
  • Cheetah - The Python-Powered Template Engine
  • SeisComP3 Seattle/Jakarta with scqc running


This section describes the installation of the binary package of QCLog. The placeholder $SC3_INSTALL_DIR must be replaced with the path to the SeisComP3 installation.

  1. Go to the home directory of the SeisComp3 installation
  1. Extract the QCLog binary package with
tar xf gempa-qclog-2015.030-jakarta-2015.020.01-ubuntu14.04-x86_64.tar.gz
  1. Generate python files from Cheetah templates
cd $SC3_INSTALL_DIR/share/qclog/files/
  1. To configure the messaging connection run the command below. Subsequently click on modules, select qcloc and set the connection.server. Finally save the changes.
seiscomp exec scconfig
  1. Login in as root user
  2. Change into Apache's document root directory with
cd /var/www/
  1. Create a symlink to the front-end of QCLog
ln -s $SC3_INSTALL_DIR/share/qclog/files/html /var/www/qclog
  1. Change owner and group to permit Apache accesing the files
chown -R sysop:www-data qclog
  1. Add the following lines to the Apache configuration to register the QCLog module
<Location ~ "/qclog/(stream|admin|overview)">
        PythonPath "['$SC3_INSTALL_DIR/share/qclog/files/python'] + sys.path"
        SetHandler mod_python
        PythonHandler qc_handler
        PythonDebug On
        Options -Indexes FollowSymLinks MultiViews

<Directory "/var/www/qclog">
       DirectoryIndex qclog.html


The Apache2 site configuration files are located in the directory /etc/apache2/sites-available under Debian GNU/Linux.

  1. Login as user
  2. Start QCLog with
seiscomp start qclog
  1. To start QCLog automatically at startup run:
seiscomp enable qclog
  1. Edit the current cron tab with
crontab -e
  1. To update the overview page every five minutes add the following line
*/5 * * * * cd $SC3_INSTALL_DIR/share/qclog/files/python/ && $SC3_INSTALL_DIR/bin/seiscomp exec python > ../html/qclog.html
  1. Save the changes


Besides the SeisComP configuration QCLog uses a separate configuration file named qc_config.cfg which contains several options like for instance the RRDCache path. Depending on the install environment the path to the file needs to be adopted to get QCLog running. The file path can be changed here: $SC3_INSTALL_DIR/seiscomp3/share/qclog/files/python/ Available options are:

Option Descritpion
RRDpicturepath [1] Path to store the generated pictures
RRDpicturepathhtml Link-path(html) for generated pictures
RRDpath Index- and rrd-file directory
config Path of this config file
RRDbinarypath Path to the binaries of qclog, for generating pictures, etc.
[1]The www-data user needs write access to the specified directory



qclog inherits global options.


-h, --help

show a help message and exit


set for the old Qcmessage


load the stations out of the inventory and create all rrd's and index-files(Overwrite old rrd's) Default:write the rrd- and index-files on the fly