Getting started

To use the cluster, you should log in to the front end, called orion.sapac.edu.au, which is a dual processor Sun Ultra 80 running Solaris. The front end should be used for compiling, debugging and testing jobs, and for submitting production jobs to the cluster. You should never need to log on to a node of the cluster, only to the front end.

You must use ssh (secure shell) to log in to orion, and sftp (secure FTP) to transfer data. If you have not used ssh before, see the primer below for a brief guide on how to use it.

Please read the rest of this User's Guide before you try to run any jobs on the cluster, particularly the sections on compiling programs and running jobs,

Accounts are set up with a default .cshrc file which invokes a global .cshrc file

  /usr/local/lib/scripts/cshrc.global

that sets all the appropriate paths and environment variables for the software on Orion. If you want to change the default .cshrc file in your account, make sure that it still calls this global .cshrc file.

NOTE: You should avoid putting commands in your .cshrc file that write output to the screen, since this may affect some utilities that use rsh. If you wish to make changes to your .cshrc file but are unsure as to how to effect the changes, contact the SAPAC helpdesk.

Using SSH and SFTP to access Orion.

SSH stands for Secure SHell, and is a secure replacement for telnet, rlogin and rsh, i.e. it is for logging in to a remote machine. The standard ssh packages also provide sftp and scp, which are secure replacements for ftp and rcp, i.e. for transferring data to and from a remote machine.

If ssh is not available on your machine, you can ask your systems administrator to install it, or install it yourself. You can download a ssh client for Unix from http://www.openssh.com/. You can download a ssh client for Windows from http://www.chiark.greenend.org.uk/~sgtatham/putty.

On Orion we are using openssh version 3.1p1. Older versions of ssh may not be compatible with this one, so you may need to upgrade.

Using ssh and sftp is simple. To connect to Orion from the SAPAC domain:

For a Unix based computer, just use,

   ssh orion 
   sftp orion 

If you are outside the sapac.edu.au domain, you will of course need to specify the complete hostname:

   ssh orion.sapac.edu.au    
   sftp orion.sapac.edu.au

If your username on Orion is different to your username on the machine you are logging in from, you need to specify your username on Orion:

   ssh username@orion.sapac.edu.au
   sftp username@orion.sapac.edu.au

The process for a Windows based computer using the Putty ssh client is similar but slightly different in that the connection is done through a fairly self-explanatory GUI. Please read the accompanying documentation or consult your systems administrator.

The first time you connect, ssh may tell you that you have not connected to this host before, and ask if it should go ahead and connect.

   ssh username@orion.sapac.edu.au
     Host key not found from the list of known hosts.
     Are you sure you want to continue connecting (yes/no)? yes
     Host 'orion' added to the list of known hosts.
     username@orion's password: 
     Last login: Tue Sep 26 10:16:48 2000 on tty1

NOTE - make sure you type "yes" not just "y":

Using SCP to transfer data to and from Orion.

Another utility ssh provides is scp, which works exactly the same way as rcp. To copy a file to your home directory on Orion, use:

   scp myfile.dat username@orion:

Note the ':' at the end. You can also specify a directory where you want the file to go:

   scp myfile.dat username@orion:/oriona/mydir

or a new name for the file, as with the standard cp command:

   scp myfile.dat username@orion:/oriona/mydir/mynewfile.dat

There is a GUI based scp client for Windows based computers that has a "drag and drop" facility and a useful inbuilt file editor. It can be obtained from http://winscp.net/eng/index.php

Using XWindows applications with Orion.

If you wish to run an xterm or another XWindows application such as pgprof from a Unix based computer, you will need to enable X forwarding. This is done from a Unix based machine by passing the -X option to ssh.

 ssh -X username@orion.sapac.edu.au

For Windows based computers you will also need a Windows XServer running. For advice, contact the SAPAC helpdesk.

Orion User's Guide