Introduction to the CrossGrid Testbed

1
Introduction to the CrossGrid Testbed

• George Tsouloupas
• UCY HPCL

2

• What is the CrossGrid testbed ?
• A collection of distributed computing resources
• Supporting a Grid environment
• Objectives
• Development, Testing and validation
• Emphasis on interoperability with EU-DataGrid
  (EDG)
• Extension of GRID across Europe

3
Testbed Overview

• A collection of distributed computing resources
• 16 sites (small large) in 9 countries,
  connected through Géant NRN
• 115 CPUs (Worker Nodes)
• 4 TB (Storage Elements)
• Grid Services Middleware (based on Globus)
  RB, VO, RC
• A group of people and resources make up the
  CrossGrid Virtual Organization (VO) and trust
  each other through national Certification
  Authorities.

4
Testbed resources
Network
5
The Local Testbed

• We currently have
• 1 CE (apelatis.grid.ucy.ac.cy) 2xPIII 1.2GHz 1GB
• 1 SE (se001.grid.ucy.ac.cy) 2xPIII 1GB 40GB
• 1 UI (thales.grid.ucy.ac.cy) P4 2GHz 1GB 40GB
• 4 WN (wn001-004.grid.ucy.ac.cy) P4 2GHz 1GB 40GB
• CA
• LCFG Installation server

6
CURRENT local testbed status
local testbed
7
Grid Security

• Security is a primary concern when it comes to
  Grids.
• The Grid Security Infrastructure is based on
  Public Key Infrastructure.
• A user is authenticated based on possession of a
  private key (known only to the user).
• Authorization depends on whether the user's
  certificate is signed by an accepted
  Certification Authority (In our case the CyGrid
  CA)
• The gridmap-file at the target resource will
  determine the if a resource will accept a
  specific user, and specifies a mapping to a local
  user

8
Crossgrid CA's
9
Obtaining a certificate

• Create a certificate request file Under Globus
  use command grid-cert-request Or using openssl
  command    openssl genrsa -des3 -out
  user.key  openssl req -new -x509 -days 365
  -key user.key -out user-req.crt DN Format  
    person   "/CCY/OCyGrid/OHPCL/CNuser
  name"   machine   "/CCY/OCyGrid/OHPCL
  /CNhost/machinename.ucy.ac.cy"
• Send by email your request file to
  cygrid-ca_at_ucy.ac.cy and your RA
  hpcl_at_ucy.ac.cy DO NOT delete either the key
  file or the request file. It is the sole copy
  of your private key, Most importantly keep it
  secure!
• You will receive your certificate which is good
  for one year.
• Install your certificate on the User Interface
  machine.

10
Job Submission
CrossGrid/Datagrid Services
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Running a Job

• User logs in on the UI
• User issues a grid-proxy-init and enters his
  certificate's password, getting a valid Globus
  proxy
• User sets up his JDL file. Example JDL of the
  hello world job
• Executable "/bin/echo"
• Arguments "Hello World"
• StdOutput "Messagge.txt"
• StdError "stderr.log"
• OutputSandbox "Message.txt","stderr.log"

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Running a job

• User issues a dg-job-submit HelloWorld.jdl
• and gets back from the system a unique Job
  Identifier (JobId)
• User issues a dg-job-status ltJobIdgt
• to get logging information about the current
  status of his Job
• When the OutputReady status is reached, the
  user can issue a dg-job-get-output JobId
• and the system returns the name of the temporary
  directory where the job output can be found on
  the UI machine.

13
Introduction to LCFG

• George Tsouloupas
• UCY HPCL

14
What is LCFG?

• Local ConFiGuration system
• A tool for installation and configuration of
  large scale, diverse, dynamically changing
  systems.
• Installs an RPM based Linux system and configures
  it.
• Config of entire site held in source files on
  central server
• Each machine defined by exactly one profile.
• Profile constructed for each machine
• Utilise inheritance
• Based on RPM lists, key-value pairs

15
LCFG Server Components
16
How LCFG Works in One Slide.
Abstract configuration parameters for all nodes
stored in a central repository
A collection of agents read configuration
parameters and either generate traditional config
files or directly manipulate various services
17
LCFG Installation

• Custom install Red Hat 6.2 including
• NFS, web server
• Install LCFG RPMs and directory tree
• Configure web server
• Populate RPM repositories
• Make root filesystem available over NFS
• Configure DHCP server
• Create client profiles

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Profiles

• A profile contains a list of RPMs to be installed
  and configuration data
• Located in /var/obj/conf/profile/source.
• Edit site-cfg.h gt globus.conf , info-mds.conf,
  gdmp.conf and others.
• Files testbed001-testbed004 are sample UI, CE, SE
  and WN. Rename one, e.g. apelatis.
• Edit apelatis hostname and hardware.include
  "AIC_ComputingElement-cfg.h"...update.modlist
  eepro100update.mod_eepro100 alias eth0
  eepro100update.rootpwd hj4aJkf\k45

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Profiles (cont)

• Contents of "AIC_ComputingElement-cfg.h"
• include "ComputingElement-cfg.h"
• update.rpmcfg CE_AIC7xxx-rpm
• update.disks sda
• update.bootdisk sda
• update.dopartition_sda yes
• update.partitions_sda sda2 sda1 sda3
• update.pdetails_sda1 64 /boot
• update.pdetails_sda2 free /
• update.pdetails_sda3 1000 swap

20

• Questions ?
• ...then more examples on
• prometheus.grid.ucy.ac.cy
• (our LCFG server)