Today I will again embark on the journey that is Upgrading Oracle. This will be the third and final time that I do this on our test system in preparation to upgrade our Production Cluster that also has a DataGaurd Backup solution. I expect this process to take a about 4 hours including the removal of the current Oracle 10 software that I have installed on the server. I am running through this from the very beginning and expect to hit no road bumps this time around. If all does go well this time then I will start to plan how I am going to handle the production environment and how much downtime I am going to require. I will require downtime since we are doing an in place upgrade. It would be nice to have enough disk to install 10 on one Cluster node and upgrade the Database files while moving them to a new disk location and then failing over the cluster once that is complete. I, however, will have to upgrade the files in place and use only the DR server as a backup. That should not be a problem though. I think I will upgrade one node bring the DB up and then install Oracle on the second node. Once that is complete the Cluster should be done. Then in a day I will upgrade the DataGaurd server as well and re-enable the replication.