Andrew McNab - Manchester HEP - 24 May 2001

WorkGroup H: Software Support• Both middleware and application support• Installation tools and expertise• Communication (web, mail lists)• Documentation and software repositories• Contacts with Globus• Middleware API definitions• Management of Grid partitions• Getting it all to actually work ...

Andrew McNab - Manchester HEP - 24 May 2001

Can we fix it?

Yes we can!

(Subject to available resources …)

Andrew McNab - Manchester HEP - 24 May 2001

Installation Tools• Three layers of software:

– a. Operating system - automated tools exist– b. Grid middleware - eg our RPM distribution– c. Applications - currently, the experiments all

use different distribution methods• a / b / c don’t need to use same mechanisms, but

they must work together.• Need to be able to specify dependencies in the

lower layers.

Andrew McNab - Manchester HEP - 24 May 2001

Interfaces with other groups• Overlap with WorkGroup D (Fabric and Data)• Need to agree package formats that will plug into

fabric management systems.• EU DataGrid WP4 (Fabric) is currently defining

installation formats for EDG Testbed 1 - clearly this will be a major influence on LHC experiments’ policies.

• What about Babar / CDF / D0?• Clearly, we need a flexible standard.

Andrew McNab - Manchester HEP - 24 May 2001

Installation proposal• Carry on using RPM’s

– Support for source and binary packaging– Dependencies– Natural for Redhat Linux etc.– Portable to Solaris etc

• RPM is where WP4 seems to be going.• Where necessary, use dumb tools to translate tar

files to RPM - this mostly applies to HEP applications.

Andrew McNab - Manchester HEP - 24 May 2001

Support for installation etc• WG-H provides support to local

administrators - ultimately “helpdesk”?

• This means that we develop of pool of expertise within WG-H about common problems which everyone can draw on.

• Important to communicate bugs, design faults etc back to Middleware and Application authors.

Andrew McNab - Manchester HEP - 24 May 2001

Communication Tools

• Website - www.hep.grid.ac.uk – Allows write access using Grid authentification.

• Mailing lists - ukhepgrid and ukhep-globus

• In other Open Source projects, WWW and lists allow users to aid in development.

• We should implement searchable list archives on the web, and make it easy for subgroups to start their own lists.

Andrew McNab - Manchester HEP - 24 May 2001

Documentation• Need formal documentation if the Grid is to

become pervasive (ie not just something for experts.)

• This is also something to offer for the Dissemination effort.

• Call these “Guides”? XYZ User Guide, XYZ Installation Guide etc.

• But also need informal HOWTO’s for experts, which can keep up with rapidly changing code.

Andrew McNab - Manchester HEP - 24 May 2001

Software repository• A central place where code (and documentation)

can be stored and shared.• Access via CVS and Web.• Nightly builds? Problem reporting to module

contact person?• What about copyright issues? Follow same practice

as Globus: if you contribute patches you are granting a COGS-compatible license?

Andrew McNab - Manchester HEP - 24 May 2001

Contacts with Globus• Globus have opened up their internal developer

lists and CVS.• This means we can already participate in their

development process to help with things we need.• We’ve also made direct links, partly via our

participation in EU DataGrid.• Globus appears very open to external collaborators,

and the best way to get specific work done may be to send people to ANL or ISI to contribute effort?

Andrew McNab - Manchester HEP - 24 May 2001

“Upper Middleware” API

• WG-H also has to draw together the various API’s from other WorkGroups to specify the environment available to Applications.

• By agreeing common API’s for access to things like meta data, other WorkGroups can produce general components (eg super schedulers) with aren’t tied to a specific experiment’s database structure.

Andrew McNab - Manchester HEP - 24 May 2001

Management of “partitions”• Especially near the beginning, we’re going to have

incompatible requirements on what is installed.• Short term solution is to divide the prototype Grid

into appropriately configured partitions.• Should bear this in mind when deciding on fabric

management and installation mechanisms.• Want to be able to reinstall machines in a partition

in an automated, reliable way.• In principle, this can be done in a few minutes.

Andrew McNab - Manchester HEP - 24 May 2001

Summary• Most of the component activities of WorkGroup H

have already been started:– Installation tools (RPM’s)– Web site– Mailing lists– Contacts with Globus

• But documentation, co-ordination of API’s and “active” support are still just starting.