DIRAC Configuration

The DIRAC Configuration information has a hierarchical structure and can come from different sources. This section describes the main sections of the DIRAC configuration and the way how this information is delivered to the consumers.

Configuration structure

The DIRAC Configuration is organized in a tree structure. It is divided in sections, which can also be seen as directories. Each section can contain other sections and options. The options are the leafs in the configuration tree, which contain the actual configuration data.

At the top level of the Configuration tree there are the following sections:

DIRAC
This section contains the most general information about the DIRAC installation.
Systems
This section provides configuration data for all the DIRAC Systems, their instances and components - services, agents and databases.
Registry
The Registry contains information about DIRAC users, groups and communities (VOs).
Resources
The Resources section provides description of all the DIRAC computing resources. This includes computing and storage elements as well as descriptions of several DIRAC and third party services.
Operations
This section collects various operational parameters needed to run the system.

The top level sections are described in details in dedicated chapters of the guide.

Configuration sources

The DIRAC Configuration can be defined in several places with strict rules how the settings are resolved by the clients. The possible configuration data sources are listed below in the order of preference of the option resolution:

Command line options

For all the DIRAC commands there is option ‘-o’ defined which takes one configuration option setting. For example:

dirac-wms-job-submit job.jdl -o /DIRAC/Setup=Dirac-Production
Command line argument specifying a CFG file

If a filename with the .cfg extension is passed as an argument to any DIRAC command it will be interpreted as a configuration file. For example:

dirac-wms-job-submit job.jdl my.cfg
$HOME/.dirac.cfg
This is the file in the user’s home directory with the CFG format
$DIRACROOT/etc/dirac.cfg
This is the configuration file in the root directory of the DIRAC installation
Configuration Service
Configuration data available from the global DIRAC Configuration Service

The client needing a configuration option is first looking for it in the command line arguments. If the option is not found, the search continues in the user configuration file, then in the DIRAC installation configuration file and finally in the Configuration Service. These gives a flexible mechanism of overriding global options by specific local settings.