N10-009 Question 191
Single answerDocumentation: Physical vs. logical diagrams, Rack diagrams, Cable maps and diagrams, Network diagrams (Layer 1, Layer 2, Layer 3)A network administrator is preparing for a weekend change window to replace a failed access switch in a remote office. The replacement switch has already been shipped to the site, and a nontechnical facilities employee will physically install it while the administrator guides the process over the phone. The administrator needs documentation that will most directly help the employee place the switch in the correct rack position and reconnect each patch cable to the proper switch ports with the least risk of error. Which documentation should the administrator provide?
- A
A Layer 3 network diagram showing subnets, routed interfaces, and default gateways
- B
A logical network diagram showing VLANs, trunk links, and STP relationships
- C
A rack diagram combined with a cable map/port diagram for the switch and patch panel connections
- D
A physical office floor plan showing workstation locations and wireless coverage areas
Show answer and explanation
Correct answer: C
Explanation
This scenario is about choosing documentation that supports a physical replacement task performed by someone with limited technical experience. In Network+ terms, the key distinction is between physical documentation and logical documentation. Physical documentation includes rack diagrams, cable maps, and port diagrams, which are used to show where equipment is mounted and how cables are connected. Logical documentation, such as Layer 2 or Layer 3 network diagrams, focuses on how traffic flows, how VLANs and routing are structured, and how the network is segmented. For a switch swap, best practice is to provide a rack diagram for placement and a cable map or port diagram for reconnection accuracy. This reduces downtime, avoids mispatching, and supports change management by ensuring the replacement matches the documented physical topology.
- A. Incorrect.
Incorrect. A Layer 3 diagram is useful for understanding IP subnets, routing paths, and gateway placement, but it does not provide the physical installation details needed for a remote hands replacement. It would not tell the employee where in the rack to mount the switch or which patch cable belongs in each switch port.
- B. Incorrect.
Incorrect. A logical diagram is helpful for understanding how the network operates conceptually, such as VLAN assignments, trunking, and spanning tree relationships. However, it is not the best document for a nontechnical person performing physical re-cabling. Logical diagrams typically abstract away exact rack units, patch panel ports, and cable identifiers.
- C. Correct.
Correct. A rack diagram shows the physical location of equipment in the rack, including the proper rack unit placement for the replacement switch. A cable map or port diagram shows exactly how ports on the switch connect to patch panel ports or other devices, often using labels and cable IDs. Together, these documents provide the most practical guidance for accurate physical installation and reconnection during a hardware swap.
- D. Incorrect.
Incorrect. A physical floor plan can help identify where users, offices, drops, and wireless access points are located in the building, but it does not usually provide the detailed rack elevation or port-by-port cabling information required for replacing a switch in the wiring closet.