Kindly be informed that we are planning to install two operation manager v 9.00 on two clustered servers (Active, Passive), and we currently have 156 OS agent licenses, So in this case should we install the 156 OS agent license on both clustered servers? Or should we buy a 156 failover OS agent licenses, and if none of the previous mentioned is correct? Please provide us with the right approach.
For your configuration you would not need to purchase the non production fail-over licenses, since you already have the production licenses in place.
You can request free agent licenses for the passive OM Management Server from the Password Delivery Center.