Downloading your Observations to your Laptop by using the DfsExport
Tool software
Date: 16-09-05
NOTE: currently installed for trial on wgsoff5 only.
SETUP FOR A NEW VISITOR:
On the visitor laptop
(download to a single laptop only, per UT is permitted):
1. The vistor laptop must have java 1.4 (run java -version and verify)
2. The visitor laptop must be connected to the blue cable (not the
wireless LAN).
3. You must know the IP of the visitor laptop - (it changes) - for
linux run "ifconfig" on the laptop to find the assigned IP
4. Create a local directory for the software (for example):
> mkdir ~/dfs
> cd ~/dfs
5. Download the dfsexport software to the laptop and save it in the
software directory (e.g. ~/dfs):
You can download it here (it is in the format
of .jar)
6. Create a directory for saving dowloaded data:
> mkdir ~/mydata
7. Start the download tool on the laptop AND leave it running:
> java -jar ~/dfs/dfsexport.jar ~/mydata 134.171.224.15 6666
The IP numbers of offline WSs are as follows:
wgsoff1
134.171.224.3
wgsoff2
134.171.224.4
wgsoff3
134.171.224.6
wgsoff4
134.171.224.13
wgsoff5 (trial offline WS)
134.171.224.15
On wgsoff5 as astro2:
1. Edit ~/.dfsexport.rc - set RECEIVER.IP keyword to IP address of the
laptop and set KEYWORD.OBS.PROG.ID keyword to the full observing run of
the visitor e.g. "'075.C-0381(B)'"
2. Test the connection to the laptop:
> dfscp -testconnection
If the test connection message is not displayed on the laptop, one of
the following is likely the cause:
the dfsexport tool was configured with the wrong IP address
the laptop is running a firewall (in which case it should either
be disabled or port 6666 should be opened)
3. When ever required/desired data may be copied to the laptop using
dfscp, e.g.:
> dfscp /data-ut1/raw/2005-06-05/*.fits
If the process on the laptop is stopped transfers will stop.
GENERAL INFORMATION:
The DfsExport tool is a simple means to export data from the offline
workstation to the visitor laptop.
The intention is to provide an easy means of getting data to the
visitor to enabling them to start work on the science data using their
own tools while at the telescope.
The tool comprises of two applications:
- DfsExport command-line tool run on the offline workstation for
sending a file to a configured visitor laptop. The DfsExport command is
wrapped in the dfscp script, which permits sending multiple files.
- DfsImport process which runs on the visitor laptop. The process is
started and left running for the duration of the download (or all
night).
The key aspects of the software for exporting data to visitor laptops
are:
- cross-platform to accommodate the range of laptops visitors run
- outbound connections from control LAN only (the laptop has no access
to the control)
- small download and configuration time to run client (DfsImport) on
visitor laptop
- easy integration of DfsExport software into offline WS software:
scripts, Gasgano and dataSubscriber.
- communications error handling and guaranteed data delivery are not
important - if a file fails to send or is truncated, it is enough that
it is resent by hand.
DfsExport/dfscp (software on offline
WS):
The sending of files to the visitor laptop requires the following
information to DfsExport:
- the path of files to send, which is supplied on the command line
- the host IP and port running DfsImport, which is given in the
configuration file.
DfsExport reads a PAF (Param) format configuration file
$HOME/.dfsexport.rc which contains the IP and port of the DfsImport
process, as well permits configuring the program id of the visitor.
This keyword will restrict sending of FITS and TFITS files to those
with the OBS.PROG.ID value given in the configuration file, or
calibration data (defined as TFITS and FITS data containing no
OBS.PROG.ID keyword, or where OBS.PROG.ID is for a period <= 60).
All non FITS and TFITS data may be sent without check. This is a very
mild form of security to restrict the visitor from exporting the
incorrect data from the offline WS.
DfsExport is a java application comprising of the following JAR
libraries:
- dfsexport.jar - the library for DfsExport/DfsImport code.
- dfs.jar - stripped down jar file containing Param/Configuration
reading classes from OHS code and FITS reading classes from Gasgano
dfs.jar.
- gnu-regexp.jar - required for OHS code, though not used.
DfsExport is called indirectly from dfscp.
DfsImport is a java application comprising of the dfsexport.jar file.
This is the only download required to run the tool on the visitor
laptop.
The laptop must be installed with Java 1.4 runtime, which is likely if
P2PP is installed.
DfsImport (software for visitor laptop):
The 6666 is a port number used by DfsImport. If for some reason there
are conflicts using 6666 another may be specified, however the
configuration file of DfsExport must also be updated with the alternate
port number.
Once running the program will wait for connections from the specified
IP number and download data as sent by DfsExport/dfscp on the offline
workstation.
The output for DfsImport should resemble the following:
"Waiting for connections."
DfsImport will not overwrite an existing file and will report an error.
DfsImport will receive a closed connection (and display an error) when
sending a file that already exists on the laptop.
Comments and feedback are welcome: Nick Kornweibel (nkornwei@eso.org)