Which statement about VLAN configuration is true?
The correct answer is A. The switch must be in VTP server or transparent mode before you can configure a VLAN.
VLANs (Virtual Local Area Networks) are used to logically segment a switch into multiple broadcast domains. This segmentation allows you to better manage network traffic and improve network performance.
To configure VLANs on a Cisco switch, you must first ensure that the switch is in VTP (VLAN Trunking Protocol) server or transparent mode. VTP is a Cisco proprietary protocol that allows switches to share VLAN information with each other, allowing for consistent VLAN configuration across multiple switches.
When a switch is in VTP server mode, it can create, modify, and delete VLANs and advertise them to other switches in the same VTP domain. In contrast, when a switch is in VTP transparent mode, it can create, modify, and delete VLANs, but it does not advertise them to other switches. Instead, it only forwards VTP advertisements it receives.
Answer B is incorrect because there is no "config-vlan" mode in Cisco switch configuration. However, there is a "vlan configuration mode" that is used to create and configure VLANs.
Answer C is also incorrect because dynamic inter-VLAN routing is supported on all VLANs, not just VLAN2 through VLAN 4064.
Answer D is incorrect because switches in VTP transparent mode do not save VLAN databases to the running configuration. Instead, they maintain their own local VLAN database, which is not shared with other switches in the VTP domain.