Enabling SSH User Equivalency on Exadata Machine

Passwordless SSH configuration is a mandatory installation requirement. SSH is used during installation to configure cluster member nodes, and SSH is used after installation by configuration assistants, Oracle Enterprise Manager, OPatch, and other features.

In the examples that follow, i used the Root user but same can be done for Oracle or Grid user

Step 1 : Create all_group file

[root@node01 oracle.SupportTools]# pwd

[root@node01 oracle.SupportTools]# cat all_group

Step 2 : Generate ssh keys

[root@node01 oracle.SupportTools]# ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
The key's randomart image is:
+--[ RSA 2048]----+
| o |
| . + . |
| . = . |
| . = *. |
| o S.+. |
| . o.E. |
| .o =.. |
| .o.+. |
| .... |

Step 3 : Copy ssh keys to all nodes 

[root@node01 oracle.SupportTools]# dcli -g ./all_group -l root -k -s '-o StrictHostKeyChecking=no'
root@node01's password:
root@node02's password:
root@cell01's password:
root@cell02's password:
root@cell03's password:
node01: ssh key added
node02: ssh key added
cell01: ssh key added
cell02: ssh key added
cell03: ssh key added


 Step 4 : Validate passwordless is working 

[root@node1 oracle.SupportTools]# dcli -g all_group -l root hostname
node01: XXXXXXX
node02: XXXXXXX
cell01: XXXXXXX
cell02: XXXXXXX
cell03: XXXXXXX