OPatch finds invalid inventory. The patch storage directory '$ORACLE_HOME\.patch_storage' is present but Standalone Inventory '$ORACLE_HOME\sainventory' is not present

for the below issue follow MOS note:1477475.1

Opatch Commands Failing with Error: "OPatch finds invalid inventory. The patch storage directory '$ORACLE_HOME\.patch_storage' is present but Standalone Inventory '$ORACLE_HOME\sainventory' is not present." (Doc ID 1477475.1)

addtional note if needed : Steps To Recreate Central Inventory(oraInventory) In RDBMS Homes (Doc ID 556834.1)

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subhen_host:ORCL > /dboracle/orabase/product/11.2.0.4/OPatch/opatch lsinv
Oracle Interim Patch Installer version 11.2.0.3.4
Copyright (c) 2012, Oracle Corporation.  All rights reserved.


Oracle Home            : /dboracle/orabase/product/11.2.0.4
Oracle Home Inventory  : n/a
OPatch version         : 11.2.0.3.4
Product information    : n/a
Log file location      : /dboracle/orabase/product/11.2.0.4/cfgtoollogs/opatch/opatch2016-05-11_14-00-54PM_1.log

Patch history file: /dboracle/orabase/product/11.2.0.4/cfgtoollogs/opatch/opatch_history.txt

Lsinventory Output file location : /dboracle/orabase/product/11.2.0.4/cfgtoollogs/opatch/lsinv/lsinventory2016-05-11_14-00-54PM.txt

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There are no Interim patches installed in this Oracle Home.

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OPatch succeeded.

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for below issue also check the similar locations , i copied the missing file from other servers and it worked

subhen_host:ORCL > pwd
/dboracle/oraInventory/ContentsXML
subhen_host:ORCL > ls -tlr
total 8
-rw-r----- 1 oracle oinstall 329 May 11 14:34 comps.xml
subhen_host:ORCL > ls -ltr
total 24
-rw-r----- 1 oracle oinstall 329 May 11 14:34 comps.xml
-rw-r----- 1 oracle oinstall 618 May 11 14:36 inventory.xml
-rw-r----- 1 oracle oinstall 292 May 11 14:36 libs.xml


subhen_host:ORCL > /dboracle/orabase/product/11.2.0.4/OPatch/opatch lsinv
Oracle Interim Patch Installer version 11.2.0.3.4
Copyright (c) 2012, Oracle Corporation.  All rights reserved.


Oracle Home       : /dboracle/orabase/product/11.2.0.4
Central Inventory : /dboracle/oraInventory
   from           : /dboracle/orabase/product/11.2.0.4/oraInst.loc
OPatch version    : 11.2.0.3.4
OUI version       : 11.2.0.4.0
Log file location : /dboracle/orabase/product/11.2.0.4/cfgtoollogs/opatch/opatch2016-05-11_14-06-49PM_1.log

List of Homes on this system:

Inventory load failed... OPatch cannot load inventory for the given Oracle Home.
Possible causes are:
   Oracle Home dir. path does not exist in Central Inventory
   Oracle Home is a symbolic link
   Oracle Home inventory is corrupted
LsInventorySession failed: OracleHomeInventory gets null oracleHomeInfo

OPatch failed with error code 73