Accessing Ivy from home with Linux

If you use windoze at home, you should use putty to access Ivy. (Ivy is the name of our Unix server.)

If you use Linux you can do much better using SSH (secure shell) and the X-Window System. The following screen-shots show you how ...

Firstly, an empty desktop:

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Command (1):

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ssh-add

You can skip this step. ssh-add takes care of swapping passwords with all the remote machines I use; this means I only have to enter one passphrase, once. Notice, that ssh-add did not echo the passphrase I pasted. (If you are using OpenSSH see notes )

Command (2):

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ivy

a little script that connects to Ivy via secure shell. (There is a zip-file with all my little scripts at the end of this.)

Notice that the xterm title is updated to reflect: the new host (IVY), and the name of the new directory (/homedir/cms/ps/temp).

Command (3):

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myx

a little script that starts the programs I always use on Ivy.

The myx command has started five x-clients; they are running on Ivy under Unix but, because we are using ssh and X-forwarding, they are displaying on my Linux desktop at home. If I start more x-clients on Ivy, using the menu, or in an xterm, they will do the same. Notice that CDE (Common Desktop Environment -- Ivy's desktop) is not being used.

Starting x-clients on Ivy:

GUI programmes on Ivy:

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Closing down (1):

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Closing down (2):

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Closing down (3):

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Best xterm for Linux on Ivy

The xterms you run under CDE don't do mouse-wheel scrolling. (Windoze or Exceed isn't set up correctly to allow it.) However, at home under Linux, you need an xterm that does respond to the mouse wheel.

/usr/openwin/bin/xterm is the one to use with CDE.

/usr/local/bin/xterm is the one to use with Linux.

Zip

It isn't really a zip file, it's a tgz. Save the file and use:

    $ tar xzf little.tgz

to extract the files on your Linux box. You will have make obvious minor changes to suit your own setup.

OpenSSH Notes

If you are using OpenSSH you will have to convert your keyfiles into the RFC 4716 SSH Public Key File Format to work with Ivy. After generating your keys you can do this by:

    $ ssh-keygen -e -f public.keyfile > keyfile.for.ivy
    

You should then upload this file to Ivy and place it in your ~/.ssh2 directory. Then create a file named authorization containing the word Key followed by the name of your public key file. Both RSA and DSA keys will work. i.e.

    $ cd ~/.ssh2
    $ more authorisation
    Key id_rsa.pub
    $ ls -1
    authorization
    id_rsa.pub
    

Make sure your private key files are only readable by you or OpenSSH will ignore them. For further information see ssh-keygen(1)