deregistration_delay in aws_lb_target_group are not working if set to 0

[fangli]

Not a native English speaker, sorry for any grammatical mistakes:)

Terraform Version:
Terraform v0.11.4

• provider.aws v1.13.0

Resource: aws_lb_target_group
Parameter: deregistration_delay

Description:
Param deregistration_delay could be set to 0 in AWS web console, which means disable deregistration delay.
But if I set this param to 0 in terraform, the created target group has a 300s deregistration delay, which is the default value in AWS webconsole.

Expected Behavior: 0s of deregistration delay
Actual Behavior: 300s of deregistration delay

This ONLY happens when new targetgroup creation. In case of updating or changing, this parameter works good.

Configuration:

resource "aws_lb_target_group" "target_group_80" {
  name = "${var.project}-${var.environment}-${var.service}-80"
  port     = 80
  protocol = "TCP"
  deregistration_delay = 0
  target_type = "instance"
  vpc_id   = "${var.vpc_id}"

  health_check {
    interval = 10
    protocol = "HTTP"
    path = "/"
    port = 80
    healthy_threshold = 2
    unhealthy_threshold = 2
  }

  tags {
    Name = "${var.project}-${var.environment}-${var.service}"
    project = "${var.project}"
    environment =  "${var.environment}"
    service =  "${var.service}"
  }

}

#3152

[catsby]

Closing as duplicate of #3152, thanks for writing in!

[ghost]

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