This is the documentation for CDH 4.7.1.
Documentation for other versions is available at Cloudera Documentation.

Generating an SSH Key Pair

After installing Whirr, generate a password-less SSH key pair to enable secure communication with the Whirr cluster.

ssh-keygen -t rsa -P '' 
  Note:

If you specify a non-standard location for the key files in the ssh-keygen command (that is, not ~/.ssh/id_rsa), then you must specify the location of the private key file in the whirr.private-key-file property and the public key file in the whirr.public-key-file property. For more information, see the next section.