Cisco Certified Network Associate (CCNA) Practice Exam

To influence path selection, which command adjusts the bandwidth on an EIGRP router?

1. show interfaces

2. bandwidth LOWER BANDWIDTH NUMBER

3. show ipv6 eigrp neighbors

4. no ipv6 eigrp AS NUMBER

The correct answer is: bandwidth LOWER BANDWIDTH NUMBER

The command that adjusts the bandwidth on an EIGRP router is specifically designed to influence the path selection process by affecting the metrics used in EIGRP calculations. By using the command to set a new bandwidth value, network administrators can alter how EIGRP perceives the link's capacity. EIGRP uses several metrics for path selection, including bandwidth, delay, reliability, load, and MTU. Among these, bandwidth plays a crucial role because EIGRP prefers paths that appear to have higher bandwidth. When the bandwidth is manually adjusted using this command, it effectively changes the EIGRP metric calculation for that interface. This can result in EIGRP choosing a different path for routing data packets based on the new bandwidth settings, thus allowing for greater control over traffic flow in the network. In contrast, the other options relate to different functions. For example, displaying interface information or EIGRP neighbor relationships does not influence path selection themselves; they are primarily used for monitoring and troubleshooting.