Cause
the address of the host specified could not be resolved
the address of the host specified could not be resolved
check URL
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/drgus.htm
https://community.oracle.com/message/1219656
https://community.oracle.com/message/1074661
https://community.oracle.com/message/1757959
https://community.oracle.com/message/309511
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