Initiating Teragrid Sessions

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Initiating Teragrid Sessions

• Raghu Reddy

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Outline

• Motivation
• Initial Setup
• Certificates
• Proxies
• Grid-map file entries and DNs
• Softenv for customizing your environment

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Motivation

• Now that you have an account on the Teragrid
• TeraGrid can be more than the sum of its parts
• More than single sign-on A common/consistent
  environment
• A common environment to the extent possible
• TG_CLUSTER_SCRATCH
• TG_COMMUNITY
• TG_EXAMPLES
• Setting up the initial environment can be a
  little confusing!

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Initial Setup for Authentication

• Certificates/Proxies/DNs (Terms you need to
  know)
• Certificate
• Your long term identity
• A couple of files in .globus/.pem files
• Use of Certificates/Proxies allow you to login
  without worrying about passwords on all the
  different platforms on the TG
• Proxy
• Your short term identity
• This is what is used to do authentication without
  passwords with globus tools such as gsissh, tgcp,
  globus-url-copy, etc.
• DN (Distinguished Name)
• Certificates and Proxies have your DN encoded
  in them
• Grid-mapfile
• Various TG hosts have your DN in their
  grid-mapfile if you are authorized to use that
  particular resource

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How do you get a Proxy?

• Using a long term certificate
• The easiest way is to start is to get a
  Certificate on one of the NCSA Teragrid Resources
  (done just once)
• Login to an NCSA system
• Use grid-cert-request command (use help for
  help)
• The DN from NCSA cert is already included in the
  grid-mapfiles of appropriate platforms
• Once you have certificate, you use
  grid-proxy-init to get a proxy
• Using a KCA proxy
• If you have an account at any of the sites that
  have KCA, then you can get a proxy without
  getting a long term certificate
• The sequence of commands are
• Kinit user_at_SITE.EDU kx509 kxlist p
• With this approach, you will have to add your DN
  to the gridmap file of various resources. The
  User Portal will simply this process in the
  future

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Accepted Certificates Authorities

• Currently the Teragrid Accepts the following CAs
• Italian Grid
• Japan AIST
• Dutch Grid
• UK E-Science
• NCSA
• PSC (No long term User Certs)
• SDSC
• TACC
• USC (No long term User Certs)
• Purdue
• DoE

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Myproxy Repository

• How do you get a Proxy at resource where you
  dont have a certificate?
• If you dont want to manage your certificates at
  multiple resources, you can use the myproxy
  server to store your proxy, and retrieve from
  another site.
• Detailed talk on this subject on Wed 1100 AM
• Alternatively you can use KCA as mentioned before

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For more information

• If you are just getting started, a good place to
  start for authentication issues is
• http//www.teragrid.org/userinfo/access/login.php

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Softenv

• What is Softenv The .soft file
• A way to manage working env on different
  platforms
• Makes it easy for users to change env (PATH etc.)
• Makes it easy for admins to add new software
• Most of the time you dont need to worry about it
• You manage this by editing the .soft file in
  your home directory
• Equivalent to the .cshrc or the .bashrc files
  you already know about!

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Example

• Suppose you want to use Totalview-2.3 instead of
  the default Totalview
• Add totalview-2.3 to the top of the .soft
  file
• Next time you login, this will be the default
  totalview you get
• If want it to take effect this session, then you
  run the command resoft
• Even if the admins change the default, this is
  the one you will be getting when you run totalview

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What does the .soft file contain?

• The .soft file can consist of the following
• Comments Begin with , similar to most shells
• This is a comment in a .soft file
• Packages Allow you to add specific software
• hdf4
• Macros To set a bunch of values
• _at_teragrid-basic
• Env variables
• PATH HOME/bin
• What Macros/Keywords are available?
• Use the softenv command to get a listing

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What Else?

• Like any scripting language, there is more!
• Pre defined env variables
• Conditional statements
• Softenv commands such as
• resoft
• soft add
• Etc.
• For additional information
• The man page man softenv-intro
• http//www.teragrid.org/userinfo/softenv/softenv-i
  ntro.html

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• Questions?