1 Introduction

Welcome to the EOS Diamond Bundle WIKI pages!

This pages will describe how to configure a Diamond XRootD gateway in front of a CEPH RADOS instance.

There are two deployment scenarios:

Front-end gateways - you configure a dedicated set of machines as protocol gateways in front of your RADOS pool. You should configure a basic ALIAS for these machines.

Overlay gateways - you configure each OSD to be an XRootD gateway. In this model you can reduce the bandwidth within the storage by 50% when reading and and 25% for writing (2 replica case). This requires an additional plug-in (CMS) which is not yet part of the bundle but in evaluation. You should configure a basic ALIAS for all OSDs.

You can configure the XRootD gateways to use a dedicated CEPH id and ideally a pair of pools for data and metadata depending on the LFN prefix used (f.e. /atlas can map to the pool diamond-atlas-data/diamond-atlas-metadata while /cms can map to the pool diamon-cms-data/diamond-cms-metadata aso.). This will become clear in the configuration pages.