DATA HANDLING

revised 17/09/01

By default observers get tapes, DDS1 90m 2.0Gb without compression or DDS3 125m 12.0Gb without compression. If an observer requires the data on CD 650 Mb he/she should tell the SA (best in advance!). Luis can then be asked for blank CDs. Follow this instructions for writing CDs: http://www.ing.iac.es/~cfg/services/cd.html Data stored at sea level machines must first be copied to the mountain (eg /scratch/fs1a) as the link to sea level is too slow with 2Mb/sec (the writing process requires an uninterrupted data flow). Writing observing data you might need more than one CD. There is no script or utility to help you with this task! The available space on each blank CD is about 650 MBytes, so the data to be saved on each CD shouldn't exceed this size. The ING is in a position to write Book 2 DVDs using the Pioneer DRM 7000 towers, however we do not maintain a stock of media. Contact Luis in case an observer requires writing data to his blank DVD.

Tape writing

Check whether the drives need cleaning, in that case a LED will flash every 4 seconds. The cleaning cartridge is placed together with the empty tapes together with instructions on how to use it.
insert tape in the drive
open a xterm session and change directory to the data directory
prompt>fitsinit - follow the screen instructions on how to initialise the tape
prompt>fitsout - again follow the instructions on the screen. Note that a list of missing runs will appear on the screen before the writing process begins.
When the writing is done, the tape will eject automatically.
Rather than fitsinit/fitsout observers often prefer
tar -cvf (device) *.fit

Alternatively, the observer can choose to write the data using tar:

*Para leer o grabar en una cinta datos reducidos:

   tar -cvf (device) ./(directorio) = Escribe los datos y las
subestructuras.
   tar -xvf (device) = Lee los datos de la cinta y las subestructuras.
   tar -tvf (device) = Hace un listado del contenido de la cinta.
   mt -f (device) offline = Rebobina la cinta.
   mt -f /dev/rmt/0bn status (eom) = Para ver como esta el device
   mt -f /dev/rmt/0bn rewind = rebobina la cinta sin sacarla
   mt -f /dev/rmt/0bn eom = lleva la cinta al final de lo grabado
   mt offline = rebobina y saca la cinta del device
   mt -f /dev/rmt/0bn bsf 4 = rebobina cuatro posiciones
   mt -f /dev/rmt/0bn fsf 4 = mueve hacia delante 4 posiciones

FTP area

In case your observer wants to ftp the data somewhere, use our ftp area:

Copy the runs from the /obsdata directory to /pub/outgoing
Data can now be fetched via ftp from ftp.ing.iac.es/pub/outgoing