What strategy is utilized when multiple servers are added during times of high usage?

The correct strategy when multiple servers are added during times of high usage is scaling horizontally. This approach involves increasing the number of servers to distribute the load among them, thereby improving system performance and reliability. Horizontal scaling allows for better resource utilization by spreading requests across multiple machines instead of relying on an individual server.

When additional servers are deployed, they can handle more simultaneous connections and processing tasks. This is particularly beneficial in cloud environments, where resources can be dynamically provisioned based on demand, allowing businesses to maintain performance during peak usage periods without overloading any single server.

In contrast, vertical scaling involves adding resources to a single server, such as CPU or RAM, which can lead to a point of limitation and is often more expensive and less flexible compared to horizontal scaling. Load balancing is a technique used to distribute incoming requests across multiple servers to ensure optimal use of resources but does not inherently involve the addition of servers. Over-provisioning refers to allocating more resources than are usually needed to absorb fluctuations in workload, which is not specifically related to adding servers during high usage times.