Cisco Catalyst 9300交换机上的AP1/0/1接口是个啥？

先看交换机输出

C9300-Stack#sh int description | in up
Gi0/0                          up             up       
Gi1/0/1                        up             up       
Gi1/0/2                        up             up       
Gi1/0/3                        up             up       
Ap1/0/1                        up             up       

C9300-Stack#show int ap1/0/1
AppGigabitEthernet1/0/1 is up, line protocol is up (connected) 
  Hardware is App-hosting Gigabit Ethernet, address is dc05.3946.d029 (bia dc05.3946.d029)
  MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec, 
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 1000Mb/s, media type is App-hosting port
  input flow-control is on, output flow-control is unsupported 
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input never, output 00:00:00, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     0 packets input, 0 bytes, 0 no buffer
     Received 0 broadcasts (0 multicasts)
     0 runts, 0 giants, 0 throttles 
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 0 multicast, 0 pause input
     0 input packets with dribble condition detected
     182681 packets output, 13559927 bytes, 0 underruns
     Output 7 broadcasts (154650 multicasts)
     0 output errors, 0 collisions, 1 interface resets
     0 unknown protocol drops
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier, 0 pause output
     0 output buffer failures, 0 output buffers swapped out

简单来说，这个接口相当于交换机内部为运行特定应用而准备的一个“虚拟网卡”。从你的 show interfaces ap1/0/1 输出也能看到，它的硬件类型是 App-hosting Gigabit Ethernet，这说明它是一个用于承载应用流量的内部接口。

它的主要用途包括：

运行思科IOx应用：在Catalyst 9300系列交换机上，可以通过IOx平台运行一些第三方或自定义的应用程序。这个 AppGigabitEthernet 接口正是这些容器化应用与交换机网络进行通信的通道。

作为嵌入式无线控制器（EWC）的数据接口：部分Catalyst 9300交换机支持“嵌入式无线控制器”功能，可以直接管理无线接入点（AP）。在这种情况下，交换机本身就像一个无线控制器，而这个内部接口就用于处理控制器功能相关的数据流量，让交换机内部的无线控制功能可以与网络通信。