Introduction Out-of-place patching builds a brand new Oracle home that already contains the Release Update, then moves the cluster or the database over to it. The old home stays untouched on disk, so the running environment is never modified and going back is a matter of pointing at the old path again. This guide patches a two-node Oracle 19c RAC from the base 19.3 release to 19.33, covering both the Grid Infrastructure home and the Database home, with each node switched one at a time so the database stays available on the other node. The sequence is: capture a baseline, install the new Grid home with the RU applied, switch Grid on Node 1, install the new Database home, switch the database on Node 1, switch Grid on Node 2, run datapatch once, and verify. Prerequisites Check the following before starting. A working two-node Oracle 19c RAC at the base 19.3 release, with the Grid home at /u01/app/grid/19c/grid_1 and the database home at /u01/app/oracle/19c/db_1 . The oracl...