opmnctl start: failed. Can not resolve test.oracle.com for interface any

ERROR

OPMN ERROR:
———-
Can not resolve test.oracle.com for interface any 
opmnctl start: failed.

SOLUTION

The issue usually occurs due to improper entries in the /etc/hosts file,
Validate your /etc/hosts and verify the loopback entries (127.0.0.1),

The loopback address should be in the below format.
127.0.0.1        localhost.localdomain localhost

If still you have the issue, verify the your network adapters using ifconfig -a