Swestore-dCache

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Revision as of 12:45, 27 October 2011 by Jonas Lindemann (LUNARC) (talk | contribs) (Center storage)
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SNIC is building up a storage infrastructure to complement the computational resources

Many forms of automised measurements can produce large amounts of data. In scientific areas such as high energy physics (the Large Hadron Collider at CERN), climate modelling, bioinformatics, bioimaging etc., the demands for storage are increasing dramatically. To serve these and other user communities, SNIC has appointed a working group to design a storage strategy, taking into account the needs on many levels and creating a unified storage infrastructure, which is now being implemented.

National storage

The aim of the nationally accessible storage is to build a robust, flexible and expandable system that can be used in most cases where access to large scale storage is needed. To the user it should appear as a single large system, while it is desirable that some parts of the system are distributed across all SNIC centres to benefit from the advantages of, among other things, locality and cache effects. The system is intended as a versatile long-term storage system.

Support: swestore-support

Center storage

Centre storage, as defined by the SNIC storage group, is a storage solution that lives independently of the computational resources and can be accessed from all such resources at a centre. Key features include the ability to access the same filesystem the same way on all computational resources at a centre and a unified structure and nomenclature for all centres. Unlike cluster storage, which is tightly associated with a single cluster and, thus, has a limited life-time, centre storage does not require the users to migrate their own data when clusters are decommissioned, not even when the storage hardware itself is being replaced.

To make the usage more transparent for SNIC users a set of environment variables are available on all SNIC resources:

SNIC_BACKUP – the user's primary directory at the centre (the part of the centre storage that is backed up)

SNIC_NOBACKUP – recommended directory for project storage without backup (also on the centre storage)

SNIC_TMP – recommended directory for best performance during a job (local disk on nodes if applicable)