Cisco Certified Network Associate (CCNA) Practice Exam

Why is it necessary to reset a switch before adding it to the network in a VTP environment?

1. To clear old VLAN configurations

2. To initialize the VTP version

3. To enable trunk mode

4. To apply the current configuration

The correct answer is: To clear old VLAN configurations

Resetting a switch before integrating it into a network in a VLAN Trunking Protocol (VTP) environment is essential primarily to clear old VLAN configurations. When a switch is previously used in another network context, it can retain old VLAN information, which may conflict with the current VTP domain settings or the VLAN configurations that are intended for the new environment. By resetting the switch, you ensure that it operates with a fresh configuration that accurately reflects the VLAN setup and information that is being propagated by the VTP server within the current network. This action prevents any potential misconfiguration or network issues that may arise from remnants of old VLAN data that the switch might otherwise use. It also helps maintain the integrity of the VTP process, ensuring that the switch synchronizes properly with the VTP advertisements it receives from other switches in the network. The other responses reference actions or settings that are not directly tied to the primary reason for resetting the switch in a VTP context. Initializing the VTP version, enabling trunk mode, or applying the current configuration are important steps in managing a switch in a VTP environment, but they do not address the fundamental need to eliminate potentially outdated VLAN configurations that could disrupt network operations.