The NGS runs an Information Service for the National Grid Service using BDIIv5 from the EGEE project. It retrieves data from NGS sites by querying the Grid Resource Information Service (GRIS) or site BDII at each site and makes it available via an LDAP server.

The data is presented using the Glue v1.3 schema, with the sematics of the attributes defined by the NGS and EGEE/WLCG project documentation.

The sites being published for the NGS top level BDII can be reviewed on line. A subset of the gLite WMS compatible sites information is also available for use by the NGS UI/WMS service.

Querying the BDII

The NGS BDII service is on the server bdii.ngs.ac.uk running on port 2170 (This replaces the deprecated ngsinfo.grid-support.ac.uk running on port 2135). It is primarily intended for the automatic discovery of resources, although its output may be queried on the  command line if an OpenLDAP client is installed by running a command such as:

[user@localhost]$ ldapsearch -x -h bdii.ngs.ac.uk -p 2170 -LLL -b "mds-vo-name=local,o=grid"

Alternatively its output may be viewed by using a program such as the commercially available Softerra LDAP Browser if you are running Windows.

Compatiblity with EGEE Information Publishing

The NGS is a heterogeneous Grid network, with sites supplying GRIS information from a variety of middlewares (VDT, Globus and gLite) and on a variety of operating systems (SL, RHEL, CentOS, Solaris, Debian, MS Windows). However all the data published by bdii.ngs.ac.uk is compatible with the homogenous EGEE/WLCG Grid top level BDII's. This is acheived by modifying the top level schemas of sites, not matching the EGEE BDII ldap schema, via an intermediate service on sitebdii.ngs.rl.ac.uk port 2170. This service is a modified gLite Site BDII installation.