AWS 最近動作頻頻，這次是更新 NLB 的新功能「Elastic Load Balancing: Network Load Balancer now supports load balancing to IP addresses as targets for AWS and on-premises resources」，9 月初才剛 ALB 才剛支援 On-Premises 環境，接連著新推出的 NLB 也支援 On-Premises 的功能了。
裡面有提到可以透過 Direct Connect，或 VPN 架構的 IPsec 來接到 On-Premises，
We are pleased to announce that Network Load Balancers can now distribute traffic to AWS resources using their IP addresses as targets in addition to the instance IDs. You can now also load balance to resources in on-premises locations reachable over AWS Direct Connect and resources in EC2-Classic. Load balancing across AWS and on-premises resources using the same load balancer makes it easy for you to migrate-to-cloud, burst-to-cloud, or failover-to-cloud.
一樣是可以混搭環境來做 Load Balancers
Prior to this launch, when using an instance ID as a target, an EC2 instance could only receive traffic from the load balancer on its primary IP address and primary network interface. This limits hosting multiple applications on the same instance where each application requires different IP address, network interface, or security group. Using IP addresses as targets removes this limitation as the load balancer can route to multiple IP addresses and network interfaces on the same instance. Load balancing using IP addresses also provides flexibility with microservice based architectures, where each application target can now use a known port instead of a random port simplifying inter-application communication. This feature also enables load balancing to your on-premises resources thereby supporting hybrid architectures.
文中沒有特別提到 VPN，而是用 Resource 的字眼，看起來應該是可以透過 VPN，可能需要 try 看看。
AWS 對於已經深耕在 On-Premises 環境的企業提供了越來越友善的導入環境，看來這塊大餅 AWS 頗積極 …
