CCNA: Cisco Certified Network Associate — Question 80

Which configuration ensures that the switch is always the root for VLAN 750?

Answer options

• A. Switch(config)#spanning-tree vlan 750 priority 38418607
• B. Switch(config)#spanning-tree vlan 750 priority 0
• C. Switch(config)#spanning-tree vlan 750 root primary
• D. Switch(config)#spanning-tree vlan 750 priority 614440

Correct answer: B

Explanation

Setting the priority to 0 makes this switch the root bridge for VLAN 750 since the lower the priority value, the higher the chance of being elected as the root. Options A and D have higher priority values, making them less likely to become the root. Option C, while effective in designating the switch as primary, does not guarantee it will be the root if another switch has a lower priority.