Particle physics computer support

New users should read this

The Computing Model

Most users have PCs on their desks running Microsoft Windows. These are used to run office applications such as email and document preparation, They are also used to run the connection program Exceed to allow connection to the physics computing servers which mostly run the Linux flavour of the Unix operating system. It is from here that most physics related computing within the sub department takes place. From both Unix and Widows users can access data and computing resources around world using the internet.

Getting Started

1. Try to get to know the Computing Support Staff. They should be able to help with any initial problems you may have and they don't bite (normally).
2. You will need accounts on both Windows and Unix.
3. For a step by step introduction to both Windows and Unix see the Introductory Computing Manual. The "Working at a PC " section of the "Getting Started" module has details on running Exceed to connect from a PC to the Unix servers. The manual also covers basics in such areas as printing as well as more advanced ones such as program development.
4. If you are familiar with the basics, then look at the other topics on this page.

Graduate Student Lectures (most are given in Michaelmas term)

2012 Lectures held on Thursdays 11:00 - 12:00 in the Fisher Room.

The Computing Facilities

• Networking and Communication. Chris Hunter
• PP Unix Overview Pete Gronbech

Linux

• Use of the local batch systems, connecting via X and ssh. Sean Brisbane

Grid Computing

• Overview
• Job submission: Low level (glite-wms) and high level (Ganga)
• Storage elements and the interfaces to them

Introduction to python and pyROOT

• Overview
• Introduction to python programming
• Using ROOT from within python
• tutorial notes

C++ Course given on Tuesday and Wednesday of Week 9

C++ Course

The C++ course will provide generic skills training in C++. C++ is widely used and a complex language that a great number of students in HEP traditionally need to use at some point in their DPhils. As C++ also contains most of the concepts used by other programming languages, a good grounding in C++ should reduce the learning curve for other languages. The course focuses on basic language and syntax training in the first day and the more advanced object orientated concepts in the second.

Students attending the course would benefit from having a few days or weeks of programming experience in one language or another, but this is not required. Students completing the course will have gained a basic grounding in:

• Overview and concepts in C++
• Creating your first program
• Basic control flow
• Logical bit-wise operators
• Introduction to functions (creating a function)
• Classes and objects
• Arrays and container classes
• Pointers
• Advanced functions (overloading, passing arrays and best practices)
• Inheritance and polymorphism

The course materials are contained in a zip file examples and slides. They are tested and working with Visual Studio 2010.

Listed below are some past lectures on programming and analysis by Nick West:

Please Note:-
The sole function of this short computing lecture course is to help new postgraduate students in PP exploit the local computing facilities effectively. As the computing environment is dynamic, the contents of this course is kept under constant review, in consultation with its intended audience.

If you have any comments about these lectures PLEASE email: p [dot] gronbech1 [at] physics [dot] ox [dot] ac [dot] uk

Who looks after what?

Useful Links

• The Unix systems in PP.
• Central IT Services
• Introductory Computing Manual by Nick West is given to all new graduate students.
• HEP Computing Topics
• C++ Course
• Oxford University Computing Services Courses are free to Staff and Students.
• Other computing training
• Central Physics Computer Pages
• Video and Audio Conferences

Remote Access

In order best to access the Windows servers in Physics, you first of all need an Internet connection. We recommend using a Broadband service for this; BT, NTL and many other providers will allow you to access the Internet from Home for a set monthly fee.

Once that is done, you can connect to physics in a number of ways:

• simple terminal type access to host computers such as PPSLGEN, ssh or WinQVT.
• X terminal access to host computers such as PPSLGEN using Vista Exceed (only via internal physics modems or VPN, Normal X windows access is blocked in the firewall)
• file transfer to/from hosts and Windows servers using SFTP
• access your mail via the web interface on the Exchange server or via one of a number of Client programs
• run applications on the Windows Terminal Server using either a Web interface or TS Client.

However, for security reasons there are some services which are not available by default. These include access to printers and restricted internal areas.

If you want transparent access to these facilities, you will need to create a VPN (Virtual Private Network) connection to Physics. For information on how to do this, see Establishing a Secure Connection using VPN (Virtual Private Networking)

If you have a very old computer or even just a terminal and a modem, you can still get terminal type access to servers within Physics by using the OUCS dialing service and selecting the telnet service.