Glue2 support in CREAM

CREAM CE provided with EMI-1 provides some initial support for glue2, that needs to be finalized

1 Target scenario

1.1 CREAM CE in no cluster mode

We assume that a CREAM CE is configured in cluster mode if that is the only CREAM CE available in the site. I.e. sites with multiple CREAM CEs (submitting to the same batch system) should always have a cluster node and therefore be configured in cluster mode.

If a CREAM CE is configured in no cluster mode, all the Glue2 object classes are published by the resource BDII running on the CREAM CE.

The ServiceId is the one specified by the yaim variable COMPUTING_SERVICE_ID (if specified). Otherwise it is ${CE_HOST}_ComputingElement.

1.2 CREAM CE in cluster mode

Sites with multiple CREAM CEs (submitting to the same batch system) should always have a cluster node and therefore be configured in cluster mode.

If a CREAM CE is configured in cluster mode:

• The resource BDII running on the CREAM CE publishes just the Endpoint and the AccessPolicy objectclasses
• All the other objectclasses are published by the resource BDII running on the gLite-CLUSTER node
• The ServiceId is the the one specified by the yaim variable COMPUTING_SERVICE_ID which is such scenario is mandatory. This variable must have the same value in all the relevant nodes (in the cluster node and in all the CREAM CEs)

-- MassimoSgaravatto - 2011-06-21