1. Information System Virginia Martín-Rubio Pascual
RedIRIS/Red.es
Curso Grid y e-Ciencia 2010, Valencia
6- 9 Julio 2010

2. Glossary
MDS
Monitoring and Discovery Service
GLUE
Grid Laboratory for a Uniform Environment
LDAP
Lightweight Directory Access Protocol
DIT
Directory Information Tree
BDII
Berkeley Database Information Index
GIIS
Grid Index Information Server
GRIS
Grid Resource Information Service

3. How is Information Systems Used?
If you are MIDDLEWARE DEVELOPER
WMS (Workload Management System)
Matching job requirements and
Grid resources.
Monitoring systems
Retrieving information about Grid resources status and availability.
What resources are available
to the Grid?
Computing resources
Storage resources
Site and services
What is their current status?
If you are an USER
Retrieve information about
resources
where you can run your job
where you can copy your files
If you are SITE MANAGER
You “publish” the information about the
services you provide.
Un sistema de información es aquel que recolecta y centraliza la información sobre el estado de los recursos disponibles en la Grid.
Without this we would not know
* what resources are available
* what are their current status

4. BDII BDII (Berkley DataBase Information Index)
BDII has been adopted in gLite middleware as the Information System provider. It´s an evolution of the Globus Monitoring and Discovering System (MDS).
BDII is a distributed and hierarchical information system based on LDAP protocol (Lightweight Directory Access Protocol).
The data published in the Information System (IS) conforms to the GLUE (Grid Laboratory for a Uniform Environment) Schema.
Information System components:
Resource GRIS
Site level BDII
Top level BDII

5. LDAP
Network protocol designed for querying and modifying directory services.
Structures directory entries as a tree: Directory Information Tree (DIT).
Following a path from the black node to
the root of the DIT a unique name is built:
Distinguished Name (DN):
“id=pml,ou=IT,or=CERN,st=Geneva, \
c=Switzerland,o=grid”
o= grid (raíz
del DIT)
c= US c=Switzerland c=Spain
st = Geneva
or = CERN
ou = IT ou = EP
id = pml id=gv id=fd

6. GLUE: Grid Laboratory Uniform Environment
GLUE Schema
The data published in the Information System conforms to the GLUE.
GLUE: Grid Laboratory Uniform Environment
The GLUE Schema aims to define a common conceptual data model to be used for Grid resources. It is a data model to describe in a meaningful way information on grid resources (static and dynamic info):
It’s based on LDAP database model.
As result of a collaboration between the EU‐DataTAG and iVDGL projects.
Now, GLUE Schema is being mapped to an XML representation:

7. GLUE Schema Example

8. Information System Components
Top-level BDII:
collects information
from site BDIIs
At each site: a site-level BDII (site GIIS):
collects information from local GRISs
On each resource: a local GRIS:
Publishes dynamic and static information
BDII: Berkeley DataBase Information Index
GIIS: Grid Index Information Server
GRIS: Grid Resource Information Server

9. Top BDII, site BDII and GRISs connections
A user or a service can query:
The top BDII (usual mode)
LDAP servers on each site (site BDII)
- User Application
- WMS
- Monitoring Services
Top
BDII-A
Top
BDII-B
Site 1 CE
Site BDII
Site 2 CE
Site BDII
Site 3 CE
Site BDII
LFC
Local GRIS SE
Local GRIS SE
Local GRIS CE
Local GRIS RB
Local GRIS CE
Local GRIS CE
Local GRIS SE
Local GRIS
MyProxy
Local GRIS

10. Information System Monitoring
Gstat: Checks health of Information System at each site

11. Querying the Information System
BDII- MDS:
ldapsearch: LDAP CLI
lcg-infosites: simple, meets most needs.
lcg-info: support more complex queries.

12. References BDII documentation gLite: User guide
gLite: User guide
Information System: User guide
GLUE Schema documentation

13. Thanks for your attention! Questions?