如何实现不同vlan间的通信,三层交换机如何配置?

Switch(config-if)#switchport mode trunk
Command rejected: An interface whose trunk encapsulation is "Auto" can not be configured to "trunk" mode.

应该是
Switch(config-if)#switchport trunk encapsulation dot1q
Switch(config-if)#switchport mode trunk
先配置封装，再设置trunk