用Qemu模拟vexpress-a9 --- 配置 qemu 的网络功能

sudo apt-get install uml-utilities
sudo apt-get install bridge-utils

ls -l /dev/net/tun 
crw-rw-rwT 1 root root 10, 200 Apr 15 02:23 /dev/net/tun

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
#NetworkManager#iface eth0 inet dhcp
# 经过试验发现，由于我用的是虚拟机，添加了三块虚拟网卡eth0对应的是NAT连接方式，eth2对应的是桥接方式，如果
# 将虚拟机的VMnet8和VMnet1禁止掉的话，eth2就不能工作，此时下面如果是bridge_ports eth2的话，qemu就无法联网了
# 但是发现eth0让然可用，所以这里设置了bridge_ports eth0.

auto br0
iface br0 inet dhcp
   bridge_ports eth0

#!/bin/sh

echo sudo tunctl -u $(id -un) -t $1
sudo tunctl -u $(id -un) -t $1

echo sudo ifconfig $1 0.0.0.0 promisc up
sudo ifconfig $1 0.0.0.0 promisc up

echo sudo brctl addif br0 $1
sudo brctl addif br0 $1

echo brctl show
brctl show

sudo ifconfig br0 192.168.11.20  

#!/bin/sh

echo sudo brctl delif br0 $1
sudo brctl delif br0 $1

echo sudo tunctl -d $1
sudo tunctl -d $1
 
echo brctl show
brctl show

chmod +x /etc/qemu-ifup
chmod +x /etc/qemu-ifdown

./qemu-system-arm ......  -net nic,vlan=0 -net tap,vlan=0,ifname=tap0

warning: could not configure /dev/net/tun: no virtual network emulation
Could not initialize device ‘tap‘

/etc/qemu-ifup tap0