13 th May 2004LINUX, which LINUX?1 Presentation to the AB/CO Technical Committee – Linux as the Future Console O/S Alastair Bland, 13 th May 2004

13th May 2004 LINUX, which LINUX? 1

LINUX, which LINUX ?

Presentation to the AB/CO Technical Committee – Linux as the Future Console O/S

Alastair Bland, 13th May 2004


Summary of the talk

• Assumptions made during this talk• Mea Culpa• A little history• Versions, installation and support (IT and AB

responsibilities) • Which window manager ? • Which internet browser ? • System level aspects


Assumptions made during this talk

• Any Linux Console made this year will be a PS Linux console (PS + CERN/IT Redhat Linux 7.3.4 distribution)

• Any future CERN Control Center Linux Console will be a PS + CERN Enterprise Linux 3.0 distribution

(anybody going to argue with me already?)


Mea Culpa

• When the decision to use Windows Consoles for SPS Operation was made I changed my own desktop from an HPUX Workstation to Windows(unlike the person who made the decision who stayed on a Mac!)

• I only use Linux for system administration, cross compilation and hacking Windows machines into shape

• I will probably move to a Linux desktop(unlike the person who made the decision who will stay on a Mac!)


A little history (1)

• The PS moved some time ago from an IT AFS based IBM AIX platform to an IT AFS based Linux PC platform

– X terminals were only used in technical buildings.– All AIX software was ported to Linux. – The operators run programs on their own console.

• The SPS and TCR stayed on the SL NFS based HPUX workstations.

– Control rooms (PCR, TCR, Fire Station, EA) were on HP X terminals until recently when Windows PCs were deployed running the HPUX programs via Exceed.

– Some java programs (but not all!) are run natively on Windows.

– Many of the X terminals in technical buildings were replaced with Windows


A little history (2)

• Most of the reasons for the PS/CO - SL/CO technical differences have not gone away with us all being in the same group.

– Many SPS colleagues will not tolerate an operational IT dependency except for networks and databases. In particular for the HPUX world:

• The SPS has no operational file systems managed by IT

• The SPS has no operational CPU servers where IT manage updates (security etc.)

• The SPS is an AFS free zone

– Many PS colleagues will not tolerate Windows in a Control System


Linux Versions

• The current CERN Linux is a “free for download” old Redhat 7.3.4 distribution, kernel 2.4.20, with the latest security updates

• There will be two new Linux distributions at CERN

– Redhat Enterprise Linux 3.0 ($$$)• For Oracle Databases

• For Oracle Application servers

– CERN Enterprise Linux 3.0 (free)• Desktops

• Physics calculations

• Controls with Oracle clients only


Installation and Support (IT and AB responsibilities

• Nicolas De Metz-Noblat, Jean-Michel Elyn or myself will probably be the installers and maintainers of the thin PS layer above the CERN IT distribution. The PS layer adds:

– NFS mounts of the AB/CO file servers

– All AB Department AFS users + many TS and AT users

– Adding Controls specific packages (java virtual machine, surveillance, cross-compilation for Front Ends)

• IT are responsible for

– Correct functioning of Linux kernel + utilities

– Oracle client integration

– Native compiler

– Security updates (we could limit when they are applied)


Which window manager ?

• PS consoles use Motif Window Manager then the C++ Console Manager (tightly linked with the PS Oracle Configuration Database)

– there is also a Java console manager waiting in the wings• Current SPS Windows consoles use Explorer, then the Java

Yacoma Console Manager

– Programs may be run as native java– X window programs may be run on HPs or Linux

The future choice of Console Manager is beyond me!

• Note that non-operational users can choose KDE, GNOME or legacy MWM window managers at login


Which internet browser ?

• Mozilla seems to be the browser for Operation

– Can display Java applets OK– Can load Java via JAWS– Can do EDH, MMM WebMail, DFS Web Access– Can do UBS transfers!– Used also as mail reader in offices

• KDE Konqueror and the Gnome equivalent are more integrated in the Desktop environment – probably not that important for Operation


system level aspects: 3rd party software

• Who is responsible for 3rd party applications, typically for development?

– The fewer the better!– Linux system administrators do not believe in

licenses!– Often they are configured better by the people who

want them• Will a Unix system administrator polish the latest and

greatest Java IDE as well as a Java developer?

• May be better to give “sudo” root rights to the user in many cases


system level aspects: compatibility

• Basic binary compatibility between

– Lxplus / lxbatch– PS Linux Console– PS/SL Linux Servers– PS Linux Front Ends– PS/SL PC LynxOS 4.0 Front Ends

• This will not always be the case however as they will evolve at different rates


system level aspects: making the Linux Console

• The PS Linux Console already exists – therefore there is no work to be done in this area

• The current RH 7.3.4 will no longer be supported by RedHat or IT in a few months – the migration to RHEL 3.0 or CEL3 has to be done for the PS Linux Console anyway. Main difficulties are as usual:

– Recompilation/linking of C++ code– Oracle library compatibility– Exceptionally some C problems

• Help is available to port HPUX X windows applications to Linux


Screen Dump: PS Console Manager and Linux port of XCLUC


system level aspects: hardware

• Consoles can be based on CERN desktop PC or rack mountable PC as used for WorldFIP gateways

• One, two or three screens possible

– Two is easier than three as can use normal AGP graphic card

• Should be possible to have hardware timing for mission critical consoles! AB/CO/HT are working in this direction


Conclusion

• Linux Consoles running CERN Linux• AFS available but not used for operation• Operation uses NFS file system for applications,

configuration• Java and Legacy C/C++ code runs natively on the

Console

Questions?

Documents

13 th May 2004LINUX, which LINUX?1 Presentation to the AB/CO Technical Committee – Linux as the Future Console O/S Alastair Bland, 13 th May 2004