安装Bridge工具软件包

Linux可以工作在网桥模式，必须安装网桥工具bridge-utils，运行命令：

　　yum install bridge-utils 或 apt-get install bridge-utils

Linux KVM Bridge逻辑结构图

通过命令行创建Bridge

注意：通过命令创建的Brdge在重启后会自动丢失，因此需要在网络配置文件中写入Brdge配置。

# 创建brdge br0# brctl addbr br0# 将br0绑定到ens33
# brctl addif br0 ens33

通过网络配置创建创建Bridge

CentOS系统：https://zhidao.baidu.com/question/1046233341920860299.html 

Ubuntu Bridge配置示例

auto ens33iface ens33 inet manualauto br0
iface br0 inet static
           address 192.168.1.2
           network 192.168.1.0
           netmask 255.255.255.0
           broadcast 192.168.1.255
           bridge_ports eth0
           bridge_bridgeprio 32767
           bridge_portprio eth0 129
           bridge_fd 5

参数

IFACE OPTIONS

       A   little  explanation  on  the  new  options  that  can  be  used  on
       /etc/network/interfaces to setup the bridge, so you don't  have  to  go
       and look at the scripts...

       bridge_ports interface specification
              this option must exist for the scripts to setup the bridge, with
              it you specify the ports you want to add to your bridge,  either
              using  "none" if you want a bridge without any interfaces or you
              want to add them later using brctl, or a list of the  interfaces
              you want to add separated by spaces, for example:
              bridge_ports eth0 eth4
              You  should  not  put any lines to configure the interfaces that
              will be used by the bridge, as this will be setup  automatically
              by the scripts when bringing the bridge up.

              If you need to specify the interfaces more flexibly, you can use
              the following syntax (most useful on a Xen dom0):
              bridge_ports regex (eth|vif).*
              This means to evaluate (as in  egrep(1))  the  expressions  that
              follow  after  "regex"  until  either  the  end  or  a "noregex"
              statement is reached.  The  regular  expressions  are  evaluated
              against all local interfaces and those that match are added.

              Specifying  "all"  is  short  for  "regex  eth.*  em.*  p[0-9].*
              noregex" and will get all the ethX and  biosdevname-format  (emX
              and pX) interfaces added to the bridge.

              Carrying this to the extremes, the following is valid syntax:
              bridge_ports all regex if.0 noregex ext0 regex vif.*
              This will add all ethX interfaces, the ifX0 interfaces, the ext0
              interface and all vifX interfaces.

       bridge_ageing time
              set ageing time, default is 300, can have a fractional part.

       bridge_bridgeprio priority
              set bridge priority, priority is between 0 and 65535, default is
              32768,  affects  bridge  id,  lowest priority bridge will be the
              root.

       bridge_fd time
              set bridge forward delay to time seconds,  default  is  15,  can
              have a fractional part.

       bridge_gcint time
              set  garbage  collection interval to time seconds, default is 4,
              can have a fractional part.  Available on Linux kernel  versions
              < 2.6.0.

       bridge_hello time
              set  hello  time  to  time  seconds,  default  is  2, can have a
              fractional part.

       bridge_hw MAC address
              set the Ethernet MAC address of the bridge to the specified one.
              There  were some concerns of how this was done in the past, see:
              http://bugs.debian.org/271406 but we are doing it on a  new  way
              now that shouldn't be as bad, see: http://bugs.debian.org/725786
              however you should know what you are  doing  before  using  this
              option.

       bridge_maxage time
              set  max  message age to time seconds, default is 20, can have a
              fractional part.

       bridge_maxwait time
              forces to time seconds the maximum time that the  Debian  bridge
              setup  scripts  will  wait  for  the  bridge ports to get to the
              forwarding status, doesn't allow factional part. If it is  equal
              to 0 then no waiting is done.

       bridge_pathcost port cost
              set  path  cost  for a port, default is 100, port is the name of
              the interface to which this setting applies.

       bridge_portprio port priority
              set port priority, default is 32, affects port id, port  is  the
              name  of  the interface to which this setting applies.  On Linux
              kernels older than 2.6.0 the max value is 255, the default  128.
              Newer kernels have a maximum value of 63 and a default of 32.

       bridge_stp state
              turn  spanning  tree protocol on/off, state values are on or yes
              to turn stp on and any other thing to set it  off,  default  has
              changed  to  off  for security reasons in latest kernels, so you
              should specify if you want stp on or off with this  option,  and
              not rely on your kernel's default behaviour.

       bridge_waitport time [ports]
              wait for a max of time seconds for the specified ports to become
              available, if no ports are specified  then  those  specified  on
              bridge_ports  will be used here. Specifying no ports here should
              not be used if we are using regex or "all" on  bridge_ports,  as
              it wouldn't work.