You need your SSH public key and you will need your ssh private key. Keys can be generated with
The private key must be kept on Server 1 and the public key must be stored on Server 2.
This is completly described in the manpage of openssh, so I will quote a lot of it. You should read the section 'Authentication'. Also the openSSH manual should be really helpful: http://www.openssh.org/manual.html
Please be careful with ssh because this affects the security of your server.
Contains the private key for authentication. These files contain
sensitive data and should be readable by the user but not acces-
sible by others (read/write/execute). ssh will simply ignore a
private key file if it is accessible by others. It is possible
to specify a passphrase when generating the key which will be
used to encrypt the sensitive part of this file using 3DES.
Contains the public key for authentication. These files are not
sensitive and can (but need not) be readable by anyone.
This means you can store your private key in your home directory in .ssh. Another possibility is to tell ssh via the
-i parameter switch to use a special identity file.
Selects a file from which the identity (private key) for RSA or
DSA authentication is read. The default is ~/.ssh/identity for
protocol version 1, and ~/.ssh/id_rsa and ~/.ssh/id_dsa for pro-
tocol version 2. Identity files may also be specified on a per-
host basis in the configuration file. It is possible to have
multiple -i options (and multiple identities specified in config-
This is for the private key. Now you need to introduce your public key on Server 2. Again a quote from
Lists the public keys (RSA/DSA) that can be used for logging in
as this user. The format of this file is described in the
sshd(8) manual page. This file is not highly sensitive, but the
recommended permissions are read/write for the user, and not
accessible by others.
The easiest way to achive that is to copy the file to Server 2 and append it to the authorized_keys file:
scp -p your_pub_key.pub user@host:
host$ cat id_dsa.pub >> ~/.ssh/authorized_keys
Authorisation via public key must be allowed for the ssh daemon, see
man ssh_config. Usually this can be done by adding the following statement to the config file: