Question

A retail company runs an e-commerce API on a Compute Engine managed instance group behind an external HTTP(S) load balancer. During periodic bot-driven traffic surges, the backend autoscaler adds many VMs to absorb the load, causing large unexpected compute spikes on the monthly bill even though the surge traffic is malicious and returns no revenue. The team wants to reduce cost during these events without degrading legitimate customer performance. What should they implement?

Accepted Answer

Enable Cloud Armor Adaptive Protection with a security policy that rate-limits and blocks the detected malicious traffic at the load balancer edge before it reaches the backends

Answer

Lower the managed instance group's maximum number of instances so the autoscaler cannot add VMs during surges

Answer

Switch the backend VMs to Spot VMs so that surge capacity is billed at a lower rate

Answer

Increase the autoscaler's target CPU utilization so fewer VMs are added during traffic spikes