WaitCondition & Creation Policy

• EC2 will send signal to cfn when the status is ‘CRETE_COMPLETE’, but it doesn’t mean all the resource is ready (e.g. bootstrapping in EC2 takes extra time)
• WaitCondition & Creation Policy are ways that we can get around this default limitation

Signal

• configure CFN to hold until for timeout/ ‘x’ number of success signals
  • if success signals received.. create_comple
  • if failure signal received.. creation fails
  • if timeout is reached.. creation fails
• use Creation Policy & WaitCondition to build the signals

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• usually use Creation Policy for EC2/ ACG, which is a default resource ready to use

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• waitcondition is a separate logical resources for more advanced data flow features