[INS-21003] Installer has detected that an invalid inventory pointer location file was specified - Oracle 12c

I was installing Oracle 12.1.0.1 Database  software in a preparation of upgrading Oracle EBS R12.2 Database from version 11.2.0.3 to 12.1.0.1. When i started Installer from the stage location then it encountered error related to Inventory "[INS-21003] Installer has detected that an invalid inventory pointer location file was specified.."

Error Stack from the Installation log file:

INFO: Setting value for the property:id in the bean:configcmd
INFO: Setting value for the property:platformcmdmap in the bean:configcmd
INFO: Setting value for the property:id in the bean:configcmd
INFO: Setting value for the property:platformcmdmap in the bean:configcmd
INFO: Setting value for the property:id in the bean:configcmd
INFO: Setting value for the property:platformcmdmap in the bean:configcmd
INFO: Setting value for the property:id in the bean:configcmd
INFO: Setting value for the property:platformcmdmap in the bean:configcmd
INFO: Setting value for the property:configcmds in the bean:configcmdmappings
SEVERE: [FATAL] [INS-10102] Installer initialization failed.
   CAUSE: An unexpected error occured while initializing the Installer.
   ACTION: Contact Oracle Support Services or refer logs
   SUMMARY:
       - [INS-21003] Installer has detected that an invalid inventory pointer location file was specified..
Refer associated stacktrace #oracle.install.commons.util.exception.DefaultErrorAdvisor:37
INFO: Advice is ABORT
SEVERE: Unconditional Exit
INFO: Adding ExitStatus FAILURE to the exit status set
INFO: Finding the most appropriate exit status for the current application
INFO: Exit Status is -1
INFO: Shutdown Oracle Database 12c Release 1 Installer

Cause:

Installer is looking for additional information in a central Inventory.  Parameter "inst_group" is missing from the file "/etc/oraInst.loc"


Solution:

Add the valid group  for "inst_group" in "/etc/oraInst.loc"

[root@erpnode3 ora_test]# cat /etc/oraInst.loc 
#inventory_loc=/u01/ora_prod/oraInventory
inventory_loc=/u01/ora_test/oraInventory
inst_group=dbaerp
[root@erpnode3 ora_test]# 

This issue can occur on machine where earlier oracle software is Installed and has a missing entry of "inst_group" parameter in central Inventory "/etc/oraInst.loc"

After adding this parameter Installer proceeds without any Issue.

thanks,
Zaheer