aws: log when multiple subnets found in the same AZ

[AlexanderYastrebov]

#0

[szuecs]

👍

[AlexanderYastrebov]

This makes sense to have only when subnets are tagged with cluster id

kube-ingress-aws-controller/aws/ec2.go

Lines 193 to 207 in 6780b71

	if _, ok := tags[clusterIDTagPrefix+clusterID]; ok {
	retFiltered = append(retFiltered, &subnetDetails{
	id: subnetID,
	availabilityZone: az,
	public: isPublic,
	tags: tags,
	})
	}
	}
	// Fall back to full list of subnets if none matching expected tagging are found, with a stern warning
	// https://github.com/kubernetes/kubernetes/blob/v1.10.3/pkg/cloudprovider/providers/aws/aws.go#L3009
	if len(retFiltered) == 0 {
	log.Warn("No tagged subnets found; considering all subnets. This is likely to be an error in future versions.")
	return retAll, nil
	}