====== Login to the Cluster ======

In the COKA Cluster we do not use passwords, users authentication is managed by Public-key authentication, thus you need to provide us the public key corresponding to the private key stored in the computer/account you will use to login to the cluster.

===== Generating a key Pair =====

In order to generate a key pair, if you do not have one already, you can follow several guides related to different GNU/Linux distributions or other OSs: 
[[ https://www.debian-administration.org/article/530/SSH_with_authentication_key_instead_of_password | Debian]]
[[ https://help.ubuntu.com/community/SSH/OpenSSH/Keys#Generating_RSA_Keys | Ubuntu]]
[[ https://wiki.centos.org/HowTos/Network/SecuringSSH#head-9c5717fe7f9bb26332c9d67571200f8c1e4324bc | CentOS]]
[[ https://www.howtoforge.com/how-to-configure-ssh-keys-authentication-with-putty-and-linux-server-in-5-quick-steps#how-to-configure-ssh-keys-authentication-with-putty-and-linux-server-in-quick-steps | Windows]]
[[ https://coolestguidesontheplanet.com/make-passwordless-ssh-connection-osx-10-9-mavericks-linux/ | Mac OS X ]]

===== Sending the public key =====

After you have generated the key pair, you have to send us the public one (often called id_rsa.pub); we will add it to the authorized_keys for your user in the COKA Cluster front-end node.
Once we add the key, you will be notified by e-mail and later you will be able to login to the COKA Cluster front-end node.
===== Actual login =====

To actually login to the front-end node, you can just type in your shell:

<code>
ssh your_user_name@coka.fe.infn.it
</code>

<WRAP center round info 80%>
Remember that to have access to the Cluster the login request has to start from the **unife.it** network (including the [[http://www.unife.it/areainformatica/servizi/vpn | Unife VPN ]]); login requests starting from IPs outside of these networks will be ignored.
</WRAP>

<WRAP center round info 80%>
Remember that your login request has to be initiated by the same account/computer where you generated the key pair (or anyway an account/computer that you have configured in order to use the private key corresponding to the public one you gave us).
</WRAP>