Overcloud deployment timed out on "WorkflowTasks_Step2_Execution"

Issue

• The overcloud deployment timed out on WorkflowTasks_Step2_Execution:

overcloud.AllNodesDeploySteps.WorkflowTasks_Step2_Execution:
  resource_type: OS::TripleO::WorkflowSteps
  physical_resource_id: 95c5b91b-fb82-41e5-a9bc-8bfc5103a871
  status: UPDATE_FAILED
  status_reason: |
    UPDATE aborted (Task update from MistralExternalResource "WorkflowTasks_Step2_Execution" [384e5ec7-36c1-4c2a-a69c-0578b01bb145] Stack "overcloud-AllNodesDeploySteps-bjzm6swzjila" [145d6b66-51c7-4ea6-bbfc-e4275a754f7a] Timed out)

• This Mistral engine log then contains the following:

InternalError: (1153, u"Got a packet bigger than 'max_allowed_packet' bytes")

• This Mistral throws as exception like the following when executing Ansible:

SizeLimitExceededException: Field size limit exceeded [class=TaskExecution, field=output, size=352860KB, limit=16384KB]