SW間で同じVLANを利用する場合 native vlan を一致させる必要がある。
CatalystではCDPにより native vlan の不一致を検出できる
02:50:45: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on FastEthernet0/13 (146), with Rack1SW2 FastEthernet2/0/13 (1).
02:50:45: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on FastEthernet0/14 (146), with Rack1SW2 FastEthernet2/0/14 (1).
02:50:45: %CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on FastEthernet0/15 (146), with Rack1SW2 FastEthernet2/0/15 (1).
