Following are the Steps to Create Blackouts from EM Console:

1). Login to OEM 12c -> click Enterprise ->  Monitoring -> Blackouts.

2). Click on Create.

 Blackout_1

3). Enter Name, Comments, Reason and Select the Targets and click Next.

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4). Select Members Targets  to Blackout and click Next 

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5). Select TimeZone, Duration and click Next.

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6). Review the details given for Blackout and click Finish.

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7). You can see the Blackout confirmation message as shown below:

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8). Go to Targets and select the Blacked out component. You can see the target status as Black out, like as shown below. 

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