How to Route AWS ALB Traffic to a Cross-Account NLB
TL;DR Connecting an ALB to a cross-account NLB requires routing to the NLB’s private IP addresses over a shared network path. If your ALB health checks time out on a single Availability Zone after verifying route tables and security groups, the issue is likely a combination of default NLB cross-zone settings and Kubernetes pod scheduling. Sharing services across different AWS accounts often requires placing an Application Load Balancer (ALB) in one account and pointing it to a Network Load Balancer (NLB) in another. ...