Cleanup a Grid Infrastructure Installation on RAC Nodes

 In case you have a failed Grid Infrastructure setup or want to clean up RAC nodes from a 19c RAC setup, follow these steps:

Grid Infrastructure DE-INSTALLATION steps:

[Execute on All Nodes | As root user]   # $GRID_HOME/bin/crsctl stop resource -all
[Execute on All Nodes | As root user]   # $GRID_HOME/bin/crsctl stop has
[Execute on Node1 | As root user]         # $GRID_HOME/crs/install/rootcrs.sh -deconfig -force
[Execute on Node1 | As GRID owner]  # $GRID_HOME/oui/bin/runInstaller -detachHome -silent ORACLE_HOME=$GRID_HOME
[Execute on Rest of Nodes | As root user]        # $GRID_HOME/crs/install/rootcrs.sh -deconfig -force
[Execute on Rest of Nodes | As GRID owner] # $GRID_HOME/oui/bin/runInstaller -detachable -silent ORACLE_HOME=$GRID_HOME

[Execute on All Nodes | As root user]  
            # rm -rf $GRID_HOME/*
            # rm -rf $GRID_HOME/.*
            # rm -rf $ORACLE_BASE/*
            # rm -f /etc/oracle/ocr.loc
            # rm -f /etc/init.d/init.ohasd
            # rm -f /etc/inittab.crs
            # rm -rf /etc/oracle
            # rm -f /usr/tmp/.oracle/*
            # rm -f /tmp/.oracle/*
            # rm -f /var/tmp/.oracle/*
            # rm -f /etc/oratab
            # rm -rf /var/opt/oracle

Overwrite the ASM OCR Disks headers:
[Execute on Node1 | As root user]
        # dd if=/dev/zero of=/dev/oracleasm/disks/OCR_DISK1 bs=1024 count=100
        # dd if=/dev/zero of=/dev/oracleasm/disks/OCR_DISK2 bs=1024 count=100
        # dd if=/dev/zero of=/dev/oracleasm/disks/OCR_DISK3 bs=1024 count=100

Now it's good to go with a new Grid Infrastructure setup.