Examkin

Soru

Zorluk: OrtaImplementing Auto Scaling and Fault Tolerance

An online multiplayer gaming platform uses Amazon EC2 instances in an Auto Scaling Group (ASG) behind an Application Load Balancer (ALB) to run its matchmaking service. The matchmaking application requires 5 minutes to bootstrap, load assets, and become fully operational. During peak hours, sudden traffic surges cause players to experience connection timeouts. Monitoring shows that during spikes, the ASG launches new instances, but before they transition to an InService state, the existing instances become overloaded and fail health checks. In addition, outbound database registration requests from the private subnets fail when the Availability Zone hosting the single NAT Gateway experiences an outage. Which TWO configurations should a Solutions Architect implement to improve the fault tolerance and auto-scaling behavior of the application? (Select TWO.)

  1. Configure an Auto Scaling Group Warm Pool with instances in a Stopped state, and configure the default instance warmup time to match the application bootstrapping duration.Cevap
  2. Deploy a NAT Gateway in each Availability Zone, and update the route tables of the private subnets to route outbound traffic through the local NAT Gateway in their respective Availability Zone.Cevap
  3. C
    Decrease the default cooldown period of the Auto Scaling Group to 60 seconds to allow the group to launch new instances more rapidly during surges.
  4. D
    Submit an AWS Support case to pre-warm the Application Load Balancer to ensure it scales out to support the sudden connection spikes.
  5. E
    Consolidate all outbound route tables to point to a single NAT Gateway deployed in a public subnet of a separate shared transit VPC.

Cevap

Configure an Auto Scaling Group Warm Pool with instances in a Stopped state, configure the default instance warmup time to match the application bootstrapping duration, and deploy a NAT Gateway in each Availability Zone, updating the route tables of the private subnets to route outbound traffic through the local NAT Gateway in their respective Availability Zone.
To solve the 5-minute bootstrapping delay, configuring an Auto Scaling Group Warm Pool with instances in a Stopped state allows pre-bootstrapped instances to quickly transition to the InService state during surges. Setting the default instance warmup to match the bootstrapping duration prevents the scaling metrics from being skewed by instances that are not yet operational. To solve the outbound connectivity failure, deploying a NAT Gateway in each Availability Zone ensures that private subnets in each zone have a redundant, localized path to the internet, eliminating the single point of failure.

Adım Adım Çözüm

1
Analyze the auto-scaling and bootstrapping bottleneck.
The application requires 5 minutes to bootstrap. Under sudden surges, the Auto Scaling Group initiates scale-out actions, but the delay in instances transitioning to an active state causes existing instances to fail due to load.
Identifying the bootstrapping time as the root cause of health check failures and connection timeouts allows us to choose a pre-warming or lifecycle management strategy.
2
Resolve the scaling latency.
Implement an ASG Warm Pool with pre-bootstrapped instances in a Stopped state to reduce launch latency, and adjust the default instance warmup parameter to match the 5-minute bootstrapping phase.
Warm Pools keep instances in a pre-warmed state so they can enter service much faster than standard scaling. Setting the instance warmup ensures the ASG does not initiate further scaling actions before the new instances are active.
3
Analyze and resolve the outbound connectivity single point of failure.
A single NAT Gateway creates a single point of failure across Availability Zones. Outbound database registrations fail when that zone goes down.
Outbound traffic must be distributed across multiple NAT Gateways (one per Availability Zone) to provide Availability Zone-level fault tolerance.

Anahtar Kavram

Auto Scaling Warm Pools and Multi-AZ NAT Gateway Redundancy
Tahmini Süre:2m 0s
Bu soruyu puanla

Konular

Implementing Auto Scaling and Fault Tolerance