Difference between revisions of "Secure Shell"

Revision as of 07:35, 13 July 2009

Secure Shell, or SSH, is a UNIX-based command interface and protocol for securely accessing a remote computer. It is frequently used as a secure method to remotely access and manipulate files directly on a website.

SSH uses a "command-line" interface, similar to DOS. A command-line interface does not use a GUI (Graphical User Interface); instead, all commands are typed at a command prompt in a special terminal window.

Enabling SSH

By default, SSH access for your account is disabled. If you would like to enable SSH access, use the following steps:

1.Open the Secure Shell application.

2.Under the "Secure Shell" tab, click on the checkbox marked "Enable this service" and click "Next". Click "yes" when the confirmation window appears. You will be taken to the "Users" tab.

3.Enter a password for your SSH access. It must be six (6) or more characters in length. Note: The password is case-sensitive.

4.Type the password again in the confirmation box, and click on "Finish". You have now enabled SSH access for your website.

Disabling SSH

Disabling SSH access does not delete or otherwise alter any files on your website. If you wish to disable SSH access, use the following steps:

1.Open the Secure Shell application.

2.Place a checkmark beside "disable this service", and click "Apply".

3.SSH access to your website has been disabled.

The Secure Shell Tab

Once your SSH access has been enabled, the following options are available under the Secure Shell tab:

Disable this service: Putting a checkmark in this checkbox and clicking "Apply" will disable SSH access to your website. Disabling SSH access does not delete or otherwise alter any files on your website.

Secure Shell Connect Information: This section provides you with the necessary settings to connect to your website using an SSH-capable client.

The Users Tab

Once you have enabled SSH access, the Users tab will allow you to change your SSH password. You do not need to know your old SSH password to do this. To change your password use the following steps:

1.Enter your new password in the box provided. It must be six (6) or more characters long. Note: password is case-sensitive.

2.Type your password again in the confirmation box provided. Click "Apply".

3.Your password has now been changed.

Using an SSH client

To make a connection to your website using SSH, you must use an SSH-capable client. If you do not have one already, then you must download and install one. There are many SSH clients for each operating system. Some of the SSH clients available are listed below:

Windows:

Putty is a simple to use application which is available for WIndows users. You can download a copy at: http://www.chiark.greenend.org.uk/~sgtatham/putty/

Linux:

Linux has built-in SSH capabilities. For information on how to use the SSH command, type "man ssh" in a terminal window.

Macintosh OSX:

MacOS X has the standard command-line ssh client, like Linux. To use it, run the "Terminal" application located in /Applications/Utilities. For more information on how to use the SSH command, type "man ssh" in a terminal window.

Macintosh OS9:

OS9 users can download and install the MacSSH applcation at the following URL: http://pro.wanadoo.fr/chombier/MacSSH/SSH_info.html

Referring to the manual or online documentation which comes with your SSH client, establish a connection to the server listed under the "Secure Shell" tab of the Secure Shell application. To complete your login, follow these steps:

1.Once the connection has been established, you will be prompted for a user name. Type in the URL of your website (do not include "www.") and hit the [enter] key.

2.You will be prompted for your password. Type in your password and hit [enter] again.

3.You are now logged in and are presented with a welcome message, along with the terms and conditions of use. Please take the time to read this information carefully, as it may be revised periodically with important information concerning your Secure Shell access.

Shell Commands

For a list of available shell commands once you have logged in using your SSH client, type "help". If you would like detailed information on any of the commands listed, type man <commandname>, e.g.: help ls.

Below is a brief overview of some basic shell commands:

cd: Changes the current directory you are in. Use "cd .." to go to the current directory's parent folder.

help: Displays a list of commands available in the secure shell.

ls: Lists the contents of the current directory.

man: Used to display the documentation (manual) for a command, e.g.: man mv.

mv: This command is used to either move or rename files.

pwd: Displays the path to the current directory you are in.

rm: Short for "remove", this command deletes a specified file.

rmdir: This command is used to delete an entire directory.

vi, pico: These are text editors, which allow you to modify text files (such as .txt and .htm files) directly on your site.