Cisco Certified Network Associate (CCNA) Practice Exam

What defines the active virtual router in the Gateway Load Balancing Protocol (GLBP)?

1. It is the router that responds to ARP requests

2. It routes packets through the network layer

3. It monitors the status of all backup routers

4. It acts as a default gateway for all traffic

The correct answer is: It is the router that responds to ARP requests

The active virtual router in the Gateway Load Balancing Protocol (GLBP) is defined as the router that responds to ARP requests. This is crucial in a GLBP deployment because it allows for load balancing of outbound traffic while providing redundancy. When a host on the local network sends an ARP request to resolve the virtual IP address of the GLBP group, the active virtual router is responsible for answering that request. By doing this, it ensures that traffic is directed towards the active virtual router rather than a physical router, allowing for efficient use of all routers in the group. This function is essential because GLBP allows multiple routers to present a single virtual IP address to the hosts on the network, distributing traffic among them based on load balancing algorithms. Properly managing ARP requests through the active virtual router avoids issues with routing and ensures optimal traffic flow while providing seamless failover capabilities in case the active router becomes unavailable.