Oracle 11gR2 RAC Grid install includes a useful script to establish and exchange ssh keys between hosts of the cluster.
The process to set up and exchange ssh keys between hosts to facilitate unchallenged logins between trusted users has been well documented already. Oracle simply provides a handy wrapper script over the whole process.
Although the main Grid install process will set up ssh keys, this is a useful verification step to ensure all nodes are reachable, as well as a prerequisite to having the cluvfy script succeed.
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