Editing Scanco Administration (section)

====RSA and DSA Authentication====

The main advantage of setting up RSA authentication is that you will no longer have to type your password each time you access a host with ssh.  There are some technical reasons why RSA and DSA access is more secure than password access.

These instructions work on both Linux and OS-X.  

# Create your public/private key pair on your local computer
#* At the command prompt type: ssh-keygen -t rsa
#* You will be asked to create a passphrase.
#* This will create the files .ssh/id_rsa and .ssh/id_rsa.pub .  Once you have these files, you never have to repeat this step.
# Copy your public key contents into the .ssh/authorized_keys2 file on the remote server
#* You can email yourself the file .ssh/id_rsa.pub from the local computer.
#* You could do this: ssh username@remoteserver.com 'cat >> ~/.ssh/authorized_keys2' < /Users/Youruser/.ssh/id_rsa.pub
#* You can also use the ssh-copy-id utility: ssh-copy-id -i <path to public key> <destination>, e.g. ssh-copy-id -i ~/.ssh/id_rsa.pub fem@thegnu.ucalgary.ca

<u>NOTES ABOUT KEYS</u>
Remember, the "authorized_keys" file is a concatenation of public (id_rsa.pub) keys, 
and the "id_rsa" is the private key.  
Every user on every computer should only have ONE "id_rsa" file, 
but can have multiple "id_rsa.pub" files concatenated into
their "authorized_keys" file.

=====SSH Agent=====

SSH-Agent is a tool to store your passphrase so you don't have type it every time.

On OS-X, it is integrated into the system Keychain - you will be asked once if it should remember your passphrase, and after that you don't have to worry about it.

Most Linux systems also have ssh-agent configured to start with every session. You may however have to do this once:
 ssh-add ~/.ssh/id_rsa

If you find that after following the above steps to create a public-private key pair and add the public key to the destination machine, you still cannot connect or are prompted for the password, likely you need to use the above command to add your private key to your local ssh-agent.