What should a solutions architect do to accomplish this?
Provision EC2 instances in us-west-1. Switch the Application Load Balancer to a Network Load Balancer to achieve cross-Region load balancing.
Provision EC2 instances and an Application Load Balancer in us-west-1. Make the load balancer distribute the traffic based on the location of the request.
Provision EC2 instances and configure an Application Load Balancer in us-west-1. Create an accelerator in AWS Global Accelerator that uses an endpoint group that includes the load balancer endpoints in both Regions.
Provision EC2 instances and configure an Application Load Balancer in us-west-1. Configure Amazon Route 53 with a weighted routing policy. Create alias records in Route 53 that point to the Application Load Balancer.
Explanations:
Switching to a Network Load Balancer does not facilitate cross-Region load balancing and would not address the need for low latency in us-west-1. Network Load Balancers are designed for layer 4, not for cross-Region traffic distribution.
While provisioning EC2 instances and an Application Load Balancer in us-west-1 is necessary, an ALB does not distribute traffic based on the geographic location of requests without additional configuration. This option does not address latency needs effectively.
This option sets up EC2 instances and an Application Load Balancer in us-west-1 and utilizes AWS Global Accelerator to provide low-latency routing and high availability across both Regions. It enhances the user experience by directing traffic efficiently.
Although creating an Application Load Balancer in us-west-1 and using Route 53 for routing is a good strategy, a weighted routing policy may not provide the low latency and failover benefits that Global Accelerator offers, especially for users in us-west-1.