最近在研究学习Open vSwitch，准备在本地Ubuntu14.04机器上安装一下，并基于其创建一些KVM虚拟机，下面就简要记录下在Ubuntu14.04系统上安装Open vSwitch的过程。
1、由于之前安装过KVM，其在本机生成了一个名为virbr0的bridge，这里我们需要事先将其删除，否则可能会与Open vSwitch产生不兼容的问题，命令如下：
◄► virsh net-destroy default
Network default destroyed ◄► virsh net-autostart --disable default
Network default unmarked as autostarted
2、这里我们同样也不需要bridge模块：
◄► sudo aptitude purge ebtables
The following packages will be REMOVED:
ebtables{p}
packages upgraded, newly installed, to remove and not upgraded.
Need to get B of archives. After unpacking kB will be freed.
Do you want to continue? [Y/n/?] y
(Reading database ... files and directories currently installed.)
Removing ebtables (2.0.10.4-3ubuntu1) ...
* Clearing ebtables rulesets [ OK ]
Purging configuration files for ebtables (2.0.10.4-3ubuntu1) ...
Processing triggers for man-db (2.6.7.1-1ubuntu1) ...
3、下面开始安装openvswitch相关包：
◄► sudo apt-get install openvswitch-switch
4、查看下ovs的运行状况：
◄► ps -ea | grep ovs
? :: ovsdb-server
? :: ovs-vswitchd
5、查看下安装的ovs的版本：
◄► ovs-appctl --version
ovs-appctl (Open vSwitch) 2.0.
Compiled May ::
6、查看下当前ovs支持的OpenFlow协议的版本：
◄► ovs-ofctl --version
ovs-ofctl (Open vSwitch) 2.0.
Compiled May ::
OpenFlow versions 0x1:0x4
7、通过ovs创建一个网桥 br0，供kvm虚拟机使用：
◄► sudo ovs-vsctl add-br br0
◄► ifconfig
br0 Link encap:Ethernet HWaddr ::fd::e5:4b
inet6 addr: fe80::4c0a:7bff:fec6:98d7/ Scope:Link
UP BROADCAST RUNNING MTU: Metric:
RX packets: errors: dropped: overruns: frame:
TX packets: errors: dropped: overruns: carrier:
collisions: txqueuelen:
RX bytes: (0.0 B) TX bytes: (578.0 B)
通过ifconfig命令，我们发现多了一个br0网桥。
8、将物理网卡eth0添加到br0上：
◄► sudo ovs-vsctl add-port br0 eth0
这步执行后，发现无法再访问外网，不过没关系，我们可以按照如下步骤解决：
1）先清除eth0的配置：
◄► sudo ifconfig eth0
2）让br0自动获取ip地址：
◄► sudo dhclient br0
3）此时就又可以通外网了：
◄► ping www.baidu.com
PING www.a.shifen.com (119.75.217.109) () bytes of data.
bytes from 119.75.217.109: icmp_seq= ttl= time=30.9 ms
bytes from 119.75.217.109: icmp_seq= ttl= time=31.9 ms
9、最后查看下目前br0和eth0的情况：
◄► sudo ovs-vsctl show
1e6548a9-956e-4b86-b743-f8da0aa2b922
Bridge "br0"
Port "br0"
Interface "br0"
type: internal
Port "eth0"
Interface "eth0"
ovs_version: "2.0.2"