SCN Headroom is low
Oracle Database 12c Standard Edition Release 12.1.0.2.0 - 64bit Production
SYS> @scnhealthcheck.sql
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ScnHealthCheck
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Current Date: 2024/03/04 13:56:32
Current SCN: 41159214993388
Version: 12.1.0.2.0
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Result: C - SCN Headroom is low
If you have not already done so apply
the latest recommended patches right now
AND contact Oracle support immediately.
For further information review MOS document id 1393363.1