What does the term 'high availability' signify in a FortiGate setup?

High availability in a FortiGate setup signifies the configuration of multiple FortiGate devices to provide redundancy and improved reliability. This approach ensures that if one device fails or experiences issues, another device can immediately take over, minimizing downtime and maintaining the network's operational integrity.

In a typical high availability setup, devices are configured in pairs or clusters, and they can share configurations and state information. This allows for seamless failover, ensuring that services remain uninterrupted even during hardware or software failures. The use of high availability is crucial for critical business applications where network downtime can result in significant losses.

Other options, while related to network performance and management, do not specifically capture the essence of high availability. Continuous monitoring relates to performance assessment rather than redundancy, bandwidth increase refers to scaling resources, and updating software without downtime speaks to maintenance rather than the core concept of continuity provided through redundancy. Thus, the emphasis on redundancy and reliability within the context of a FortiGate setup distinctly identifies option B as the accurate definition of high availability.