COMPASS Access

to the

COMPASS testbeam data


Presently the data of the first two COMPASS testbeam periods is stored in the WA89 Exabyte EXB-120 tape robot. This data can be accessed on the WA89 offline farm (machines vsnhd2 - vsnhdg at CERN). The following procedure should be followed to use these tapes:
  1. Login onto a machine in the WA89 offline cluster.
  2. Mount the tape you want to use (e.g. tape 20):
           robot mount 20
           
    As response you can get the following answers:
    1. The tape was successfully mounted:
             Tape X5 20 mounted in drive vsnhd5 MT
             
    2. The tape is in use by someone else:
             Not authorized for tape location 1
             
    3. There is no drive free in the robot:
             No free drive available in the robot.
             
    For other messages consult the man page robot(1).
  3. In case a. you can proceed to use the tape. To do this, you have to login onto the machine given to you by the robot mount command (in our example: vsnhd5). On this machine you have to use the given device, e.g. /dev/MT to run your job on.
  4. After running your job do not forget to dismount the tape to free the drive and the tape for other users:
           robot dismount 20
           
Do not try any other way to access these tapes. Do not run jobs accessing these tapes on machines other then the one given to you by the robot mount command.


This page was updated on September 25, 1997
by Lars.Schmitt@cern.ch