Cause
MMON sub-action did not complete within the system specified time frame.
MMON sub-action did not complete within the system specified time frame.
Do not delete from WRI$_ALERT_OUTSTANDING. If this condition repeats, please contact Oracle Support.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12700.htm
https://community.oracle.com/message/3229900
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