A clustered server goes offline due to a backplane failure. Which of the following clusters does not lose capacity when a server goes offline?

In an active-passive cluster only the active node handles traffic while the passive node idles, so when the active node fails there is a transition period during which the passive node must be brought online, interrupting service.

A distributed cluster spreads workloads across locations or nodes but does not inherently guarantee uninterrupted capacity when a single node fails, as the outcome depends on the specific implementation and load balancing configuration.

In an active-active cluster every node is actively handling workloads at all times, so the failure of one server due to a backplane issue does not take the cluster offline - surviving nodes continue serving requests without a failover transition. Because no single node is designated a passive standby, the cluster maintains continuous availability even after losing a member. This contrasts with active-passive designs, where the standby node must be activated and traffic redirected before service resumes.

A standby switch cluster is not a standard server clustering model and does not describe an architecture designed to maintain full capacity upon a node failure.