DAQ: LINUX Cluster
DAQ: Online LINUX Cluster
DAQ Project list
Purpose of System
- online/daq software development
- (G)UIF for data taking, online monitoring
- workplace computers for west hall
- NOT: general user platform for private applications
System Overview
The HERA-B online LINUX cluster consists of 10 Pentium PC's
under LINUX 2.0.28. It's built up as a NFS-cluster with common
home directories and data disks mounted to the central server
machine: hb-linux - a P200 with 64MB memory, two SCSI-IFs with:
- 20 GB disk space:
- 3.5 GB home (daily incremental backup)
- /d1 and /d3: two time 4 GB data disks (NFS)
- /d2: system data disks: backups etc.
- 4 GB scratch space
- tape drives:
- 2 DATs: /dev/nst0 and /dev/nst1
- 1 DLT4000: /dev/nst2
The data disks are also accessible from the
VME LynxOs Cluster . The boot- and homedirectory
server for the VME CPUs is located on the hb-lynx machine, a server machine
operated under LINUX, very similar to the hb-linux. This machine is partially
integrated in the Online LINUX cluster.
The user machines are: hb-con01, hb-con02, ...., hb-con08
Software Installation
- CERN-libs: one installation under /home/cern.
But logical links from all machines: cern -> /home/cern
- TCL/TK: one common installation under /home/tcltk, but on all
machines all links are proper set from /usr/lib and /usr/bin
- Common HERA-B stuff: located under /home/herab
User Support / FAQ
- If you need an account , in case of questions,
if you need diskspace
or you want to mount disks from other computers, send an email:
Klaus Ehret
- Printing : a large number of DESY printers are accesible from
each LINUX node:
'lpr -P<printername> <file>'
- the reference password file is kept on the hb-linux,
only changes
on this machines get active and will automatically update
your password on all linux machines. This password file is also the
reference for the VME/LynxOs side, but there exists yet no automatic
update procedure.
- the VME/LynxOs home can be accessed under /LynxHome/<user>
- incremental backups carried out each morning at
5h am. If you have
unintentional deleted eg. a file, you may get the latest saveset
by login to the hb-linux machine:
- /save/incbackup-home-tar.Z (latest saveset of Linux homedirs)
- /save/incbackup-home-tar.Z.old (previous saveset of Linux
homedirs)
- /save/hb-lynx/incbackup-home-tar.Z
(latest saveset of LynxOs homedirs)
- /save/hb-lynx/incbackup-home-tar.Z.old (previous saveset of LynxOs
homedirs)
and extract the relevant files with tar, eg.:
tar -xzv <your file> -f /save/incbackup-home-tar.Z
the leading /home in the pathname is replaced by a dot.
- in case of problems/troubles consult either: K. Ehret,
Th. Kihm, G. Leffers, J. Zweizig or C. Hast.
Network Plans
Next Steps
- connection of server machines to fast ethernet:
- HERA-B West Hall Network Infrastructure
- extend the cluster
by several machines
- increase disk space
- try to install LINUX on notebooks to have an easy transportable
platform esp. for work near the detector
Documentation
last update 20/5/97
editor: K.Ehret