I am wondering what happens when I have a weighted routing policy set up in my rout53 pointing at two different Ec2 or ALB and the health check fails for one of them?
What happens to the traffic which is on the failed weight target? Will it fail? or route53 will send that weight also to the healthy target which will exceed the original weight assigned to the healthy targets.
TL;DR, it will ignore the unhealthy endpoint and re-calculate the weight.
For example, if you have 3 endpoints with a weight 1 for each of them. Normally, you will get 1/3 of the total traffic on each endpoint. If one of them fails the health check, then the remaining two healthy endpoints will each receive 1/2 of the total traffic.