Perform an out-of-place Oracle Restart patching by switching from the current Oracle Grid Infrastructure home to a patched Oracle Grid Infrastructure home.

1. Download the 19.3 Oracle Grid Infrastructure base release image files.
   https://www.oracle.com/database/technologies/oracle-database-software-downloads.html#19c
2. As the grid user, extract the downloaded image files into a new Oracle Grid Infrastructure home directory.

   $ mkdir -p /u01/app/oracle/product/19.17.0/grid
   $ chown grid:oinstall /u01/app/oracle/product/19.17.0/grid
   $ cd /u01/app/oracle/product/19.17.0/grid
   $ unzip -q download_location/grid.zip

   Here:

   • /u01/app/oracle/product/19.17.0/grid is the new Grid home.
   • /u01/app/oracle/product/19.16.0/grid is the old Grid home.
3. As the grid user, download and install the latest version of the OPatch utility in the new Grid home.

   https://updates.oracle.com/download/6880880.html

   $ mv /u01/app/oracle/product/19.17.0/grid/OPatch /u01/app/oracle/product/19.17.0/grid/bak_OPatch
   $ unzip latest_Opatch.zip -d /u01/app/oracle/product/19.17.0/grid/

4. Download the Oracle Database RU version that you want to apply from My Oracle Support. In this example, Oracle Database 19.17 RU.
   For more information, see, Downloading Release Update Patches
5. Start the Oracle Grid Infrastructure installer to perform a software-only Oracle Restart installation. You can apply the optional -applyRU or -applyOneOff flags to apply Release Updates (RUs) during the installation.

    $ /u01/app/oracle/product/19.17.0/grid/gridSetup.sh [-applyRU patch_directory_location]
   [-applyOneOffs comma_separated_list_of_patch_directory_locations]

6. Follow the steps in the configuration wizard to complete the Oracle Grid Infrastructure installation.
7. As the root user, run the following command to prepare the new home for the out-of-place patching:

   # /u01/app/oracle/product/19.17.0/grid/crs/install/roothas.sh -prepatch -dstcrshome
   /u01/app/oracle/product/19.17.0/grid

   This command does not shut down any services.
8. Run the following command to switch to the new Oracle Grid Infrastructure home and perform the out of place patching:

   # /u01/app/oracle/product/19.17.0/grid/crs/install/roothas.sh -postpatch -dstcrshome
   /u01/app/oracle/product/19.17.0/grid

   This command shuts down the old Oracle Grid Infrastructure home and starts resources from the new Oracle Grid Infrastructure home. All Oracle Grid Infrastructure services start running from the new Grid home.
9. Update the Oracle central inventory (oraInventory).

   $ /u01/app/oracle/product/19.17.0/grid/oui/bin/runInstaller -updateNodeList ORACLE_HOME=/u01/app/oracle/product/19.17.0/grid CRS=TRUE
   $ /u01/app/oracle/product/19.16.0/grid/oui/bin/runInstaller -updateNodeList ORACLE_HOME=/u01/app/oracle/product/19.16.0/grid CRS=FALSE

10. To switch back to the old Grid home:
    1. As the root user, run the prepatch script.

       # Old_GI_Home/crs/install/roothas.sh -prepatch -dstcrshome Old_GI_Home

    2. As the grid user, run the postpatch script.

       # Old_GI_Home/crs/install/roothas.sh -postpatch -dstcrshome Old_GI_Home

    3. Update the Oracle central inventory (oraInventory).

       $ /u01/app/oracle/product/19.16.0/grid/oui/bin/runInstaller -updateNodeList ORACLE_HOME=/u01/app/oracle/product/19.16.0/grid CRS=TRUE
       $ /u01/app/oracle/product/19.17.0/grid/oui/bin/runInstaller -updateNodeList ORACLE_HOME=/u01/app/oracle/product/19.17.0/grid CRS=FALSE