[CLUE-Tech] ssh using RSA authentication?

[David Anselmi]

Dave Price wrote:
> Hi,
> 
> I am trying to set up 'no password' access to remote systems with ssh
> and RSA keys.
> 
> I have built both rsa and rsa1 keys on a mandrake client - these have
> null passwords

Null passwords is perhaps a bad idea, but may be necessary...

On the server, you need the authorized keys file containing the public 
key you generated.  Typically it goes in ~/.ssh/authorized_keys.

Let's say you're using version 2 of the protocol (you need a recent 
OpenSSH package since old ones have security holes).  The line in 
authorized keys should look like this (and it's all one line):

ssh-rsa <pub key in base64> <comment>

That's all there is to it.

On the client side, you need the private key.  Usually that is in 
~/.ssh/id_rsa (for an rsa key).  Both pieces of the key are generated by 
ssh-keygen which you seem to have down.

So, authorized_keys on the server, id_rsa on the client (this is the one 
with the null password).

If ssh asks you for a passphrase, it is trying to decrypt your private 
key.  If it asks for a password it is skipping rsa authentication.

When you use ssh, you have to be connecting as the user with the 
authorized_keys file, use -l <username> if it is different on the client 
machine.

You can use -v (or -vv) to get details about the authentication process. 
  It's pretty helpful showing you what ssh thinks is happening.

If none of this helps, perhaps you have a different client than server. 
  For example, the CLUE server runs SSH (not OpenSSH) so it behaves very 
differently.  It should be possible to do what you're trying in that 
case, but I didn't get it to work in the short time I fiddled with it.

HTH,
Dave