Step 1 Create .SSH, and Create RSA Keys on Each Node

Log in as an Oracle/CRS user and execute bellow steps

$ mkdir ~/.ssh

$ chmod 700 ~/.ssh

$ /usr/bin/ssh-keygen -t rsa

At the prompts:

Accept the default location for the key file (press Enter).

Enter and confirm a pass phrase unique for this installation user.

Step 2 Add All Keys to a Common authorized_keys File

On the primary node (RAC1), change directories to the .ssh directory. Then, add the RSA key to the authorized_keys file.

$ cd .ssh

$ cat id_rsa.pub >> authorized_keys

$ ls

In the .ssh directory, you should see the id_rsa.pub keys that you have created, and the file authorized_keys.

Step 3 Copy authorized_key file to all cluster node (RAC2) 

$ scp authorized_keys RAC2:/export/home/oracle/.ssh/

The authenticity of host 'rac2 (192.168.0.222)' can't be established.

RSA key fingerprint is c0:1f:20:34:54:b2:cd:9f:42:f2:d6:25:36:2f:3e:db.

Are you sure you want to continue connecting (yes/no)? yes

Warning: Permanently added 'rac2,192.168.0.222' (RSA) to the list of known hosts.

Password:

authorized_keys      100% |*****************************|   221       00:00

Step 4 Log in on second node (RAC2) and Add the RSA keys for the second node (RAC2) to the authorized_keys file:

$cd .ssh

$cat id_rsa.pub  >> authorized_keys

Step 5 Copy authorized_key file to all cluster node (RAC2)

$ scp authorized_keys RAC1:/export/home/oracle/.ssh/

Step 6 Enabling SSH User Equivalency on Cluster Member Nodes. On the system where you want to run OUI, log in as the ORACLE/CRS user and execute:

$ ssh RAC1 date

$ ssh RAC2 date

$ ssh RAC1-PRIV date

$ ssh RAC2-PRIV date