MAC address of the virtual router.

Why This Happens

When a workstation sends frames to its default gateway—especially in setups like HSRP (Hot Standby Router Protocol)—it resolves the gateway's IP via ARP. The response provides the virtual router's MAC address , not the physical router's, ensuring traffic always reaches the active forwarding router without reconfiguration.

This virtual MAC (often starting with 0000.0c07.acXX) acts as a shared identity between primary and standby routers, promoting high availability. Workstations ARP for the virtual IP and get this consistent Layer 2 address.

Common Exam Context

This question appears in Cisco Networking Academy quizzes (e.g., FHRP modules). Options typically include:

  • MAC of forwarding router
  • MAC of standby router
  • MACs of both routers
  • MAC of virtual router (correct)

"The IP address of the virtual router acts as the default gateway... the MAC address... will be the MAC address of the virtual router."

Frame Flow Breakdown

  1. Workstation checks destination IP: off-subnet? → Use default gateway IP.
  2. ARP request for gateway IP → Virtual router MAC returned.
  3. Ethernet frame built: Src MAC (workstation), Dst MAC (virtual router).
  4. Active router processes frame based on matching its virtual MAC.

Without an exhibit, this assumes standard HSRP topology—two routers sharing a virtual IP/MAC for gateway redundancy, as in 2025-2026 CCNA materials.

TL;DR: Virtual router MAC ensures seamless failover.

Information gathered from public forums or data available on the internet and portrayed here.