TiersAtRAL < Atlas

---+ Introduction
 This page briefly explains what the ATLAS computing model is, what facilities are avaliable at RAL and how ATLAS users can access them.

---+ The ATLAS computing Model

*Tier 0* This is CERN where the raw data will be produced. This is archived at CERN before being distributed to the Tier 1s.

*Tier 1* There are 10 Tier 1s serving ATLAS.  RAL is the UK Tier 1 and is expected to recieve 10% of the raw data from CERN.  Tier 1 

*Tier 2* 

*Tier 3*

This page explains the computing model and the hardware that is avaliable at RAL.

---+ Tier 1
 The Tier 1 for the UK cloud is based at RAL. The Tier 1 is in the machine room in building R89.

In order to run at the Tier 1 you grid certificate must be either:
/atlas/uk/Role=production
/atlas/uk/Role=poweruser0

---+ Tier 2
 As well as the Tier 1 there is a Tier 2 cluster also based at RAL however it is in a different building from the Tier 1 and run by different people.

---+ Tier 3
The Tier 3 is actually part of the Tier 2 that has been reserved for use by RAL staff.

-- Main.AlastairDewhurst - 2009-10-09
This topic: Atlas > WebHome > TiersAtRAL
Topic revision: r2 - 2009-10-09 - AlastairDewhurst