UNIX for Dummies Questions & Answers

hello.

can somebody please idiot proff simple guide me how to set up ssh public key authenciation?

i am stuck, i tried long and googled a lot but i cant get it.

thanks in advance.

Sorry, that is a bit much you're asking for. Here are some good links where you get splendid information:

https://help.ubuntu.com/community/SSHHowto
How to set up SSH (for the beginner)

Follow them and when you come to a point where you are stuck, ask the appropriate question here.

Terms:
client machine = your desktop
server machine = the machine you will be connecting to

assumptions:
you are using linux (if not let us know your OS)
you are using openssh (and openssl)
that ssh is installed and operational on the client machine and that sshd (server daemon) is installed and operational on the server machine. Check these two points by connecting to the server machine and supplying a password when prompted. If you get a shell prompt then both ssh on the client and sshd on the server are installed and operational.

Now, on to what you want to know.

1. at the command prompt on the client machine, logged in as the user that will be making the connection, run the following command:

Code:

ssh-keygen -t rsa

this will generate a public/private RSA protocol 2 key pair. If you need passwordless authentication, then just press enter each time it asks for a pass phrase, otherwise create a passphrase for use with this key.

2. you will now have a file called id_rsa.pub in your /home/user/.ssh directory.
this needs to be copied to the server machine - use scp to do this

Code:

scp /home/user/.ssh/id_rsa.pub server:id_rsa.pub.clientmachinename

3. now connect to the server machine and sign in as usual.

4. at the prompt on the server machine do this

Code:

cd
mkdir -p .ssh
cat id_rsa.pub.clientmachinename >>.ssh/authorized_keys
chmod 700 .ssh
chmod 600 .ssh/authorized_keys

5. log out of the server machine.

6. log back into the server machine, if all goes well, you will be asked for the passphrase you set for the key pair (or you will be connected directly, without asking for the passphrase or your login password, if the key pair has no passphrease)

7. repeat from step 2 for other machines you will need to connect to from the client machine, there is no need to create more than one key pair, it can be used for all machines you connect to.

big thanks a lot, i am trying now

Good guide Wempy , I was about to post something very similar as I've spent the last week finding out those exact steps, which is all a newbie really needs to know for SSH.
The problem with the guides on the 'net is that they frequently forget the bleeding obvious such as which fragging machine is the client and which one is the server, and which commands/files go on which one.