The machine rasp-para.unice.fr (IP: 134.59.154.200) is only accessible once connected to the VPN (https://wiki.unice.fr/display/SCSIFAQ/VPN). Use the following id to login : <yourlogin>@etuval.
Once connected, the machine should answer to ssh (but not ping).
Your login/password will be handed to you during the lab session. On the first login, you have to change the default password to whatever you want.
It is strongly advised you configure a ssh public/private key authentication for future logins. For example see https://www.linode.com/docs/security/authentication/use-public-key-authentication-with-ssh/
On node01, generate a ssh pub/priv key pair and add the public key to ~/.ssh/authorized_keys. If everything is correct, you should be able to ssh without passwords to nodes0[2-4].
It's better to develop on your machine and copy the source on the cluster to test it.
scp yourcode.c <login>@rasp-para.unice.fr:~/