mac ifconfig详解

lo

 # loopback 本机主机地址
 # flag=8049:网络设备状态标识
 # UP:网卡处于启动状态
 # LOOPBACK:IP数据包回送到本机上,通常用于测试网络配置和本地程序之间通信用
 # RUNNING:代表网卡的网线被接上
 # MULTICAS:网卡可以发送多播包
 # mtu:最大传输单元(这里设置的16384是否以太网设置的？)
 lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAS> mtu 16384

 # 参数? 可以设置值
 options=1203<RXCSUM,TXCSUM,TXSTATUS,SW_TIMESTAMP>
 
 # ipv4地址 127.0.0.1 子网掩码 255.0.0.0
 inet 127.0.0.1 netmask 0xff000000

 inet6 ::1 prefixlen 128

 # ipv6地址
 inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1

 nd6 options=201<PERFORMNUD,DAD>

gif

  # software network interface 网络接口
  # POINTOPOINT: 允许2台机器点对点直连
  # MULTICAS:网卡可以发送多播包
  # mtu:最大传输单元(这里设置的1280是否以太网设置的？)
  gif0: flags=8010<POINTOPOINT,MULTICAST> mtu 1280

stf

  # stf 6to4 tunnel interface 配置隧道
  stf0: flags=0<> mtu 1280

XHC20

  # XHC20
  XHC20: flags=0<> mtu 0

en0

  # en0: 以太网0
  # flags=8863:网络状态标识
  # BROADCAST:有广播地址，支持发广播包
  # SMART:
  # RUNNING:代表网卡的网线被接上
  # MULTICAS:网卡可以发送多播包
  # mtu: 最大传输单元
  en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
	ether c4:b3:01:ce:06:11
	# ipv4地址 子网掩码 广播地址
	inet 192.168.1.11 netmask 0xffffff00 broadcast 192.168.1.255
	# 网络媒介类型 (可手动指定)
	media: autoselect
	# 激活状态
	status: active

p2p0

  # p2p0:Point-to-Point 协议
  p2p0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 2304
	ether 06:b3:01:ce:06:11
	# 网络媒介类型
	media: autoselect
	# 闲置的
	status: inactive

awdl0

  # awdl0: airdrop peer to peer(一种mesh network)，apple airdrop设备特有
  # Apple: 无线直接链接
  # PROMISC: 允许混杂的模式(全部的数据会被接口接收)
  awdl0: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1484
	ether a6:04:50:c4:66:92
	inet6 fe80::a404:50ff:fec4:6692%awdl0 prefixlen 64 scopeid 0x7
	nd6 options=201<PERFORMNUD,DAD>
	# 网络媒介类型
	media: autoselect
	# 激活状态
	status: active

en1 en2
此处为何这么多en接口呢 运行命令行networksetup -listallhardwareports 可查看具体接口是做何操作的 具体结果

  Hardware Port: Wi-Fi
  Device: en0
  Ethernet Address: c4:b3:01:ce:06:11
  
  Hardware Port: Bluetooth PAN
  Device: en3
  Ethernet Address: c4:b3:01:ce:06:12
  
  Hardware Port: Thunderbolt 1
  Device: en1
  Ethernet Address: 4a:00:07:5c:bd:00
  
  Hardware Port: Thunderbolt 2
  Device: en2
  Ethernet Address: 4a:00:07:5c:bd:01
  
  Hardware Port: Thunderbolt Bridge
  Device: bridge0
  Ethernet Address: 4a:00:07:5c:bd:00
  
  VLAN Configurations
===================

  # en1: 以太网1 雷电口1
  en1: flags=8963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
	options=60<TSO4,TSO6>
	ether 4a:00:07:5c:bd:00
	media: autoselect <full-duplex>
	status: inactive
	
	en2: flags=8963<UP,BROADCAST,SMART,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
	options=60<TSO4,TSO6>
	ether 4a:00:07:5c:bd:01
	media: autoselect <full-duplex>
	status: inactive

bridge0

  # 具体google下桥接知识
  bridge0: flags=8822<BROADCAST,SMART,SIMPLEX,MULTICAST> mtu 1500
	options=63<RXCSUM,TXCSUM,TSO4,TSO6>
	ether 4a:00:07:5c:bd:00
	Configuration:
		id 0:0:0:0:0:0 priority 0 hellotime 0 fwddelay 0
		maxage 0 holdcnt 0 proto stp maxaddr 100 timeout 1200
		root id 0:0:0:0:0:0 priority 0 ifcost 0 port 0
		ipfilter disabled flags 0x2
	member: en1 flags=3<LEARNING,DISCOVER>
	        ifmaxaddr 0 port 8 priority 0 path cost 0
	member: en2 flags=3<LEARNING,DISCOVER>
	        ifmaxaddr 0 port 9 priority 0 path cost 0
	media: <unknown type>
	status: inactive

原文:https://juejin.cn/post/6844904074303766535