Opatch lsinventory fails on 10.1.2 ORACLE HOME | Oracle Database

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When executing Opatch from Tools Oracle Home (10.1.2), you may end up with below error:

Error:

LsInventory: OPatch Exception while accessing O2O

OPATCH_JAVA_ERROR  : An exception of type "OPatchException" has occurred:

OPatch Exception:  OUI found no such ORACLE_HOME set in the environment

  Can not get details for given Oracle Home

  An exception occurs

  null

There is no Interim Patch

OPATCH_JAVA_ERROR  : An exception of type "OPatchException" has occurred:

Can not get a list of inventory on this home.

ERROR: OPatch failed because of Inventory problem.

Solution:

The error comes when Oracle Home information is missing in inventory.xml

Navigate to oraInventory directory (can be found under oraInst.loc)

cd  /etc/oraInventory/ContentsXML/

vi inventory.xml

Check if Oracle home entry is missing or incorrect in the file.

If missing Oracle Home needs to be attached so as to make entry to inventory.xml

Use below command to attachHome:

cd $ORACLE_HOME/oui/bin

./runInstaller -silent -attachHome ORACLE_HOME="/im/<inst_id>/apps/tech_st/10.1.2" ORACLE_HOME_NAME="<INST_ID>_TOOLS"