If only one web server in an auto-scaling group is under high utilization, what is most likely the issue?

In an auto-scaling architecture, a load balancer is responsible for distributing incoming traffic across multiple web servers in the group. If only one web server is experiencing high utilization while the others are operating normally, this situation typically indicates that the load balancer is not effectively distributing the incoming requests.

A misconfigured load balancer may cause it to direct a disproportionate amount of traffic to a single server, leading to high resource consumption on that server while others remain underutilized. Proper load balancing should ensure a more even distribution of traffic, preventing any individual server from becoming a bottleneck.

In this context, adjusting the load balancer settings or verifying its health checks and routing algorithms would likely resolve the issue and ensure that all servers are utilized efficiently.