Your SlideShare is downloading. ×
Grid Lingo - in glideinWMS context
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Grid Lingo - in glideinWMS context

173

Published on

This talk provides basic Grid definitions, within the glideinWMS ecosystem.

This talk provides basic Grid definitions, within the glideinWMS ecosystem.

Published in: Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
173
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
2
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. glideinWMS training The Grid lingo with a particular emphasis on the Open Science Grid. And how it relates to glideinWMS. by Igor Sfiligoi (UCSD)glideinWMS training glideinWMS - The Larger Picture 1
  • 2. Why this talk? We will be using a lot of Grid terminology in the other glideinWMS talks. This talk provides the definitions for the most used acronyms allowing you to understand those talks.glideinWMS training glideinWMS - The Larger Picture 2
  • 3. Grid computing ● Grid computing is usually defined as a federated set of HTC clusters sharing a common (set of) middleware ● There are many implementations of “Grids” ● We will concentrate on Open Science Grid (OSG) ● OSG is the most used Grid by glideinWMS (a close second is EGI, but it is quite similar to OSG)glideinWMS training glideinWMS - The Larger Picture 3
  • 4. OSG Building Blocks ● OSG is composed of a set of independent HTC cluster providers ● Also called sites ● There is no central command-and-control ● OSG organization provides to HTC operators ● A software stack, containing a well defined set of middleware packages ● A common security infrastructure, i.e. authentication and authorization mechanisms ● Plus other support servicesglideinWMS training glideinWMS - The Larger Picture 4
  • 5. OSG Software ● OSG clearly separates computing resources from storage resources ● We are only interested in computing ones for the purpose of glideinWMS ● Each HTC cluster has ● A Compute Element (CE), which OSG software submits to the local HTC system installed on all ● A set of worker nodes, where of them compute jobs runglideinWMS training glideinWMS - The Larger Picture 5
  • 6. The CE ● The CE is the only externally accessible service ● Provides an abstraction layer to the site-local HTC system ● OSG provides the Globus Gatekeeper, has recently transitioned from v2 to v5 (gt2 & gt5) ● OSG clients also support the EGIs CREAM Repository Worker node Worker node CE Scheduler Worker node Worker nodeglideinWMS training glideinWMS - The Larger Picture 6
  • 7. Security mechanisms ● OSG mandates x.509 certificates Same mechanism for service and user authentication as used by HTTPS ● Based on Public Key Cryptography (PKI) ● User is given a certificate with a unique Distinguished Name (DN) ● The user authorization is role based, and handled by VOMS ● VOMS=Virtual Organization Management System ● A service for granting extended attributesSee “Security in OSG” talk for more details http://www.slideshare.net/igor_sfiligoi/osg-school-2012-security-in-osgglideinWMS training glideinWMS - The Larger Picture 7
  • 8. What are Virtual Organizations? ● Basically, a well defined group of people sharing a common interest ● In OSG, we expect them to also have ● Some internal governance ● Appoint trustworthy security contact ● Run VO-specific services (e.g. VOMS) ● Example OSG VOs ● The High Energy CMS experiment (single science, worldwide) ● The Holland Computing Center (single location, multiple sciences)glideinWMS training glideinWMS - The Larger Picture 8
  • 9. Back to glideinWMS ● glideinWMS creates an overlay system on top of the various HTC clusters HTC ● From the VO point of view, HTC a single HTC system glideinWMS HTC HTC ● Just a dynamic one HTC ● glideinWMS HTC completely automates the process See “Larger Picture” talk for more details http://www.slideshare.net/igor_sfiligoi/glideinwms-the-larger-pictureglideinWMS training glideinWMS - The Larger Picture 9
  • 10. A little more complicated than that ● The previous slide could led you to believe that there can only be one overlay ● In reality, there can be any number of them! ● Each serving its own user community ● Not necessarily all using gwms 1 HTC the same set HTC of HTC clusters HTC gwms 2 HTC gwms 3 HTCglideinWMS training glideinWMS - The Larger Picture 10
  • 11. Why many glideinWMS instances? ● VOs typically dont want to share a glideinWMS HTC instance ● While technically possible, there are ● Security risks ● Increased maintenance complexity ● Politics! ● Typically we get one glideinWMS HTC instance per VO ● But some VOs have more than oneglideinWMS training glideinWMS - The Larger Picture 11
  • 12. Acknowledgments ● This document was sponsored by grants from the US NSF and US DOE, and by the UC systemglideinWMS training glideinWMS - The Larger Picture 12

×