NLB lost one of assigned IP adresses.

Question

Hello community.

I have a Network Load Balancer in my infrastructure. It was deployed to the two private subnets in two availability zones.  It was working well until I noted that one of the assigned internal IP addresses for inbound connections was lost. I verified that by host and dig commands.  
I found a lost IP on my Network interfaces. I can see that it is still assigned to the correct subnet and has the right interface type network_load_balancer.

My question: How can I return my IP address, or maybe network interface, to my NLB? Do you have any ideas?

Leo K · Accepted Answer

Is the DNS name that you are looking at with `dig` configured as an "alias" record in a Route 53 hosted zone? They allow an "evaluate target health" option to be enabled, which automatically removes the IPs from DNS that aren't reporting as healthy.

Particularly if your NLB or the target group is configured not to allow cross-AZ load balancing, the NLB might not have any functioning targets in a given AZ, causing its IP to be removed from DNS. The cross-AZ load balancing option is described in these documentation articles:
* https://docs.aws.amazon.com/elasticloadbalancing/latest/network/network-load-balancers.html#cross-zone-load-balancing
* https://docs.aws.amazon.com/elasticloadbalancing/latest/network/target-group-cross-zone.html

NLB lost one of assigned IP adresses.

回答を追加する

関連するコンテンツ