Central Linux Support at DESY

Because of the growing number of installations and interest in Linux, Central Computing developed a concept which will enable the groups to use Intel processor based computers running the Linux OS in a secure and DESY compliant way. Linux PCs will be integrated into the current DESY computing model.

Classes of DESY computing machines

Workgroup Server

Every workgroup server hosts a small group of users for interactive work or processing of batch jobs. A workgroup server provides local diskspace and access to central data disks and tapes. Workgroup servers can share their local data with other workgroup servers.
Workgroup servers have in common that they

• are centrally located in the computer center or special rooms,
• get full central support and monitoring,
• have fast network access,
• have access to large datasets on disk and tape,
• can share local data with other machines,
• can have a batch facility to process long running jobs,
• have powerful hardware adopted to their task,
• access user data and standard software via AFS.

Desktop computer

There is a large number of desktop computers spread all over DESY. Centrally supported are X terminals and desktop PCs running Windows NT or Linux.
Desktop PCs allow to use local applications (editor, webbrowser, office software,...) and to access workgroup servers.
All Linux desktop PCs have in common that they

• are located on the individual's desk,
• get only installation support from -IT-,
• have only standard (slow) network access,
• have no access to large datasets,
• don't share local data with other machines,
• have no batch facility to process long running jobs,
• have only standardized hardware,
• have no automatic backup (except AFS),
• access user data and standard software via AFS.

• Central support and a high security level can only be provided for centrally installed Workgroup Servers.
• Access to large datasets and sharing of data is only possible for a relatively small number of machines on a fast and dedicated network. Thus only (centrally installed) servers have access to large datasets and shared data.
• Continuous support of any hardware/OS platform requires a lot of manpower. Therefore support for different hardware configurations can only be provided for Workgroup Servers, being a small group of machines with specific needs. The large group of Desktop Computers is only supported on the "DESY Standard PC" configuration.

Details of central Linux support

Supported Intel based Linux PCs

• Centrally installed Linux Work Group Servers (computer without a local display and a keyboard which are located in a computer center or a similar safe room) with AFS-Login and AFS network filesystem for user home directories and ASG software products. Central Computing aims to provide for a setup similar to the functionality of currently supported Work Group Servers based e.g. Sun/Solaris and SGI/IRIX.
  Compute servers combined to Linux farms are supported with a setup similar to workgroup servers.
• Linux Desktop Computers running the Linux OS on the individual's desk (computers with a local display and a keyboard) using only standard hardware (as defined by the "DESY Standard PC"). Desktop Computers also use AFS-Login and the AFS network filesystem for user home directories and ASG software products.
  Nevertheless Central Computing recommends to use the DESY environment for desktops under WindowsNT whenever possible.

Installation and administration

Guidelines for installation and administration are provided by -IT- at the following locations:

• For Linux Workgroup Server: http://www.desy.de/unix/linux/linux-wgs-install.html
• For Linux Desktop Computer: http://www.desy.de/unix/linux/linux-desk-install.html

General rules are

• The names of the nominated group admininistrators have to be reported to -IT-.
• The installation and administration of the Linux machines is done by the group administrator according to the rules defined here and in the appropriate installation guide.
• for desktop systems only the "DESY Standard PC" is supported, for workgroup servers the hardware can be specific and must be agreed with the UNIX group prior to aquisition.
• System files must not be modified.
• User and root access for -IT- has to be granted at any time.
• The password for the root-account must be reported to -IT-.
• Users don't get root privileges.
• Dual boot configurations are not supported.

-IT- provides help for installation and administration of workgroup servers but no individual help for desktop computers. If a problem on a desktop computer can't be fixed by the group administrator, -IT- recommends as a first measure to reinstall the PC from the installation server.

Application Software and Environment

The DESY-HEP-Environment will be supported under Linux (Login-, Shell- and X-Support), which provides for an environment almost identical to other supported platforms (e.g. SGI/IRIX, Sun/Solaris, etc).

Mail and Printing is part of the supported functionality, similar to other officially supported (UNIX) platforms.

Security

-IT- will take care to make the relevant patches available on the central installation server as quickly as possible. The group administrators are informed by -IT- about the availability of patches and other security relevant matters.

Security updates or reinstallations of desktop computers are the sole responsibility of the group administrator. -IT- may offer help for updates of workgroup servers.

Consulting