図を参照してください。VLAN46 のユーザーは DHCP サーバーから IP アドレスを取得できません。VLAN 10 と DHCP サーバーのすべてのパラメータが正しく設定されていると仮定します。インターレース VLAN46 で、ユーザーが DHCP サーバーから IP アドレスを受信できるようにするコマンドはどれですか?
正解:C
The issue is that devices in VLAN46 cannot communicate directly with the DHCP server because they are in different VLANs (subnets). For users in VLAN46 to obtain an IP address from the DHCP server in VLAN10, the switch must act as a DHCP relay agent. This is done using the ip helper-address command. DHCP messages, such as DHCP Discover, are sent as Layer 2 broadcasts. Broadcasts do not traverse VLANs or subnets. The ip helper-address command on the interface in VLAN46 (on the Layer 3 device) configures the switch to forward DHCP broadcasts to the DHCP server's unicast address (10.221.10.10). This allows the devices in VLAN46 to get an IP address from the DHCP server in VLAN10.