What type of test assesses a Disaster Recovery (DR) plan using realistic disaster scenarios while maintaining minimal impact to business operations?

A parallel test actually activates the DR systems alongside production systems simultaneously to verify the recovery environment can handle the load, which involves significantly more operational complexity and potential business impact than a simulation.

A walkthrough (or structured walk-through) test involves team members verbally reviewing and stepping through the DR plan documentation to identify gaps, but does not involve enacting any realistic disaster scenario.

A simulation test involves enacting a realistic disaster scenario (e.g., a mock emergency) to assess how personnel and procedures respond, without actually switching over to the DR site or halting production systems. This approach tests the DR plan's effectiveness and team readiness under realistic conditions while keeping business impact minimal, making it more rigorous than a walkthrough but less disruptive than a full interruption or cutover test.

A tabletop exercise is a discussion-based review where stakeholders talk through their roles and responses to a hypothetical scenario in a conference room setting, which is less realistic and less operationally involved than a simulation test.