CTIO in conjunction with NASA, now has a satellite link to the US which is open to all users, for remote logins, copying files to or from home, and real time communications with collaborators in the US. In 3-5 years, remote observing may be possible. We encourage you to use the link and if you do, please report it in your visitor suggestions form before you leave CTIO. The equipment has been affected by the harsh 91' winter, and therefore the link has been unstable. This document explains how to log onto your computer at home, how to copy files in either direction, and instructions for copying images to your home institution. It is also possible to have collaborators in the US checking images as they are taken.

1. Remote Login

You may log onto machines at your home institution using the machine name or the internet number assigned to the machine. If you first try the name and cannot connect, use "nslookup machinename.path", to get the internet number for your machine. The UNIX command to remotely log onto other machines is "telnet". The following example shows the possible forms:

     cl> !nslookup bootes.unm.edu
     Server:  ctio.edu
     Address:  139.229.1.2

     Non-authoritative answer:
     Name:    bootes.unm.edu
     Address:  129.24.8.2

     cl> telnet bootes.unm.edu
     Trying 129.24.8.2 ...
     Connected to bootes.unm.edu.
     Escape character is '^]'.

                  +---------------------------------------------------+
                  |              University of New Mexico             |
                  | Computer and Information Resources and Technology |
                  +---------------------------------------------------+

	     The BOOTES Local Area Vax Cluster
             Local Node UNMB -- VAX 6000-320 Running VAX/VMS V5.4-2  

     Username:

You may now log onto your home machine, provided you have an account. Using the address instead of the name, "telnet 129.24.8.2", would give the same result. Typing in your username will result in a prompt for the password. You may now read mail, run programs, and edit files on your home machine. Logging off your home machine will kill the connection.

2. Copying Files

The UNIX command "ftp" is used to copy files between machines. If you have a file on your home computer that you wish to copy down to your visitor account, for example, your loginuser.cl file, do the following:

     cl> !ftp 129.24.8.2
     Connected to 129.24.8.2.
     220 BOOTES.UNM.EDU MultiNet FTP Server Process 3.0(12) at Thu
     10-Oct-91 3:01PM-MDT
     Name (129.24.8.2:username): iraf
     331 User name (iraf) ok. Password, please.
     Password:
     230 User IRAF logged into CPD:[USER.IRAF] at Thu 10-Oct-91 17:02, job
     5c6b.
     ftp> 

Since "ftp" is not normally defined as a foreign task in IRAF, you must preceed the command with a exclamation sign. Now you must go the the directory where your file resides and use "get" to pull it from your home directory to the CTIO computer. At the same time we will send a file home called backup.

     ftp> cd cpd:[user.iraf.workspace]
     250 Connected to CDP:[USER.IRAF.WORKSPACE].
     ftp> dir
     200 Port 6.65 at Host 129.24.8.2 accepted.
     150 List started.

     CDP:[USER.IRAF.WORKSPACE]
       
      LOGINUSER.CL;1      2034   2-AUG-1991 08:07 [AP$,IRAF] (RWED,RWED,RE,)
      FIRST_TRY.FITS;1    2020   2-AUG-1991 08:08 [AP$,IRAF] (RWED,RWED,RE,)
      VARS.DST;1          33   2-AUG-1991 08:06 [AP$,IRAF] (RWED,RWED,RE,)


     Total of 4087 blocks in 3 files.
     226 Transfer completed.
     295 bytes received in 0.86 seconds (0.34 Kbytes/s)
     ftp> get loginuser.cl
     200 Port 6.67 at Host 139.229.2.60 accepted.
     150 ASCII retrieve of CDP:[USER.IRAF.WORKSPACE]LOGINUSER.CL;$ started.
     226 Transfer completed.  16896 (8) bytes transferred.
     local: LOGINUSER.CL remote: LOGINUSER.CL
     16896 bytes received in 6.6 seconds (2.5 Kbytes/s)
     ftp> send backup
     200 Port 6.76 at Host 139.229.2.60 accepted.
     150 ASCII Store of CPD:[USER.IRAF.WORKSPACE]BACKUP.;1 started.
     226 Transfer completed.  620 (8) bytes transferred.
     local: backup remote: backup
     620 bytes sent in 0.0057 seconds (1.1e+02 Kbytes/s)
     ftp> quit
     221 QUIT command received. Goodbye.
     cl>

The file will be copied to the directory from which you ran "ftp". There is a help page available in UNIX by typing "man ftp" within or outside of IRAF.

3. Sending Images Home

If you have an image that you would like to get to a collaborator quickly, then you must first write the image onto disk using wfits. You should use the proper format. For a fits format disk image you must first type "binary". This will set the mode for transfer, so then type the "send" command. This works that same for getting an image from home to compare with one you have just taken, use "get imagename".

     cl> !ftp 129.24.8.2
     Connected to 129.24.8.2.
     220 BOOTES.UNM.EDU MultiNet FTP Server Process 3.0(12) at Thu
     10-Oct-91 3:01PM-MDT
     Name (129.24.8.2:username): iraf
     331 User name (iraf) ok. Password, please.
     Password:
     230 User IRAF logged into CPD:[USER.IRAF] at Thu 10-Oct-91 17:02, job
     5c6b.
     ftp> binary
     200 Type I ok.
     ftp> send image.fits
     200 Port 6.76 at Host 139.229.2.60 accepted.
     150 BINARY Store of CPD:[USER.IRAF.WORKSPACE]IMAGE.FITS;1 started.
     226 Transfer completed.  620 (8) bytes transferred.
     local: image.fits remote: image.fits
     620 bytes sent in 0.0057 seconds (1.1e+02 Kbytes/s)

If you wish to copy all of your images at the end of the night to your home computer, there are several more steps required. You should find some space on a disk to write all your nights images to fits format. Use the UNIX "tar" utility to write them all to one tar file, and use "compress" on this file. The following example shows the steps to first get the images copied to the home machine and then, what to do when you get home to retrieve the images.

     cl> cd home$tardir
     cl> wfits *.imh image
     File 1: may12.08.imh -> image001 sn1991t  B            Size = 509 x 506
     2 Header  358  Data logical (2880 byte) records written
     File 2: may12.09.imh -> image002 sn1991t  V            Size = 509 x 506
     2 Header  358  Data logical (2880 byte) records written
     File 3: may12.10.imh -> image003 sn1991t  R            Size = 509 x 506
     2 Header  358  Data logical (2880 byte) records written
     File 4: may12.11.imh -> image004 sn1991t  I            Size = 509 x 506
     2 Header  358  Data logical (2880 byte) records written
     File 5: may12.07.imh -> image005 sn1991t  U            Size = 509 x 506
     2 Header  358  Data logical (2880 byte) records written
     cl> !tar -cvf image* > images.tar
     cl> !compress images.tar
     cl> !ftp 129.24.8.2
     Connected to 129.24.8.2.
     220 BOOTES.UNM.EDU MultiNet FTP Server Process 3.0(12) at Thu
     10-Oct-91 3:01PM-MDT
     Name (129.24.8.2:username): iraf
     331 User name (iraf) ok. Password, please.
     Password:
     230 User IRAF logged into CPD:[USER.IRAF] at Thu 10-Oct-91 17:02, job
     5c6b.
     ftp> binary
     200 Type I ok.
     ftp> send image.tar.Z
     200 Port 6.76 at Host 139.229.2.60 accepted.
     150 BINARY Store of CPD:[USER.IRAF.WORKSPACE]IMAGE.TAR.Z;1 started.
     226 Transfer completed.  14432(8) bytes transferred.
     local: image.tar.Z remote: image.tar.Z
     620 bytes sent in 0.0057 seconds (1.1e+02 Kbytes/s)
     ftp> quit
     221 QUIT command received. Goodbye.
     cl>

The file is in the same form as the file on the machine here. When you return home, first you must use the UNIX "uncompress image.tar.Z". This assumes that your home machine runs UNIX. Then use "tar xvf - < image.tar". And finally you must get the images out of fits storage format by using "rfits image* raw raw oldiraf+".

4. Collaborations

We have had astronomers log in remotely from the states to look over the shoulder of their collaborator at the telescope and do data reduction while the other observed. This requires that IRAF host files be set to the proper path, especially for displaying images remotely at the US terminal. If you would like to have your collaborator looking over your shoulder while observing, you must talk with Steve Heathcote, sheathcote@noao.edu, so that the link may be set up BEFORE your observing run. There is a UNIX command "talk" which enables two people to talk to one another in one of the windows while reductions are being done in another. To use "talk" you must specify the username of the person being contacted, if you are on the same machine, or specify the username@machinename for other machines. The online help for "talk" is available by typing "man talk".