how to deinstall the failed 11gR2 grid infrastructure

Two parts are involved: first deconfigure, then deinstall

Deconfigure and Reconfigure of Grid Infrastructure Cluster:

Identify cause of root.sh failure by reviewing logs in $GRID_HOME/cfgtoollogs/crsconfig and $GRID_HOME/log, once cause is identified, deconfigure and reconfigure with steps below – please keep in mind that you will need wait till each step finishes successfully before move to next one:

For Step1 and 2, you can skip node(s) on which you didn’t execute root.sh yet.

Step 1: As root, run “$GRID_HOME/crs/install/rootcrs.pl -verbose -deconfig -force” on all nodes, except the last one.

Step 2: As root, run “$GRID_HOME/crs/install/rootcrs.pl -verbose -deconfig -force -lastnode” on last node. This command will zero out OCR and VD disk also.

Step 3: As root, run $GRID_HOME/root.sh on first node

Step 4: As root, run $GRID_HOME/root.sh on all other node(s), except last one.
Step 5: As root, run $GRID_HOME/root.sh on last node.

Deinstall of Grid Infrastructure Cluster:

Case 1: “root.sh” never ran on this cluster, then as grid user, execute $GRID_HOME/deinstall/deinstall

Case 2: “root.sh” already ran, then follow the step below – please keep in mind that you will need wait till each step finishes successfully before move to next one:

Step 1: As root, run “$GRID_HOME/crs/install/rootcrs.pl -verbose -deconfig -force” on all node, except the last one.

Step 2: As root, run “$GRID_HOME/crs/install/rootcrs.pl -verbose -deconfig -force -lastnode” on last node. This command will zero out OCR and VD disk also.

Step 3: As grid user, run $GRID_HOME/deinstall/deinstall

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