ENEA & EGEE/EGI/IGI: the Gateway Approach

 ENEA partecipation in EGEE/EGI/IGI has been focused on the interoperability between ENEA-GRID and EGEE/EGI/IGI infrastructure with the target to provide access to AIX based computational resources.

To overcome the problem of the unavailability of the EGEE middleware for the AIX worker nodes a gateway solution has been implemented and it is used to provide access to 96 AIX WN in the EGEE production infrastructure. The solution has been successfully tested also for other UNIX like platforms, as IRIX, Mac OS X, Cray and Altix systems and it presentely in production also for the CRESCO HPC system (x86_64).

The gateway implementation is based on SPAGO (Shared Proxy Approach for GRID Objects).
This approach is based on the utilization of a proxy worker node that shares a file system with the CE and the real workers nodes. The GRID middleware commands are wrapped with a remote execution command (as ssh or lsrun, in the LSF evironment) so that  when the real worker nodes execute them, the effective execution takes places on the proxy WN.

In the case of the interoperability between ENEA-GRID and EGEE/EGI/IGI SPAGO has been implemented making use of the two main component of ENEA-GRID "middleware", LSF and OpenAFS, but the same architecture has been also implemented also using other shared file systems (NFS, GPFS)  and resource managers, as PBS.

A full description of the ENEA gateway architecture and its components can be found in:

EGEE Technical Note EGEE-TR-2007-001 "The gateway approach providing EGEE/gLite access to non-standard architectures"  Bracco, G; Migliori, S; Sciņ, C. ; Santoro , A.; available as pdf document at  CERN https://cds.cern.ch/record/1057231 or as a local copy.

The utilization of OpenAFS has required the modification of the gssklog package to add the support of the VOMS features. A small modification also to the LCMAPS package has also been necessary.

The modifications to gssklog and to the LCMAPS packages are described in:

EGEE Technical Note EGEE-TR-2006-006 "AFS Pool Account Users - GSSKLOG and LCMAPS extension to support AFS users as EGEE pool account users"  Bracco, G; Giammarino, L; Migliori, S; Sciņ, C. ; available as pdf document at CERN https://cds.cern.ch/record/990369 or as local copy 

The software is available here: http://www.afs.enea.it/project/eneaegee/software/index.html

The list of the presentations related to the ENEA Gateway Approach at the EGEE/EGI/IGI related conferences can be found in the documentation section.

Other user experience in using SPAGO Approach for interoperability with a gLite based GRID:



3/10/2010 G. Bracco  [ENEA-GRID Home page] [ ENEA-EGEE/EGI/IGI Home page]