配置KVM网络桥接功能

配置KVM网络桥接功能

配置之前我们来说说网桥： 网桥设备（Bridge），相当于现在的二层交换机，将同一网段的所有机器连接起来。我们配置的网络桥接功能就是将网络设备eth0加进br0（相当于一个交换机设备）。

因此，我们需要先添加一块br0设备（相当一个二层交换机）。

一、安装生成br0的工具

[root@centos3 ~]# yum install -y bridge-utils 已加载插件：fastestmirror, langpacks Loading mirror speeds from cached hostfile * base: mirrors.njupt.edu.cn * epel: hk.mirrors.thegigabit.com * extras: mirrors.njupt.edu.cn * updates: mirrors.nju.edu.cn epel/x86_64/primary_db FAILED ETA http://hk.mirrors.thegigabit.com/epel/7/x86_64/repodata/256fe13c9b4274f5ab2b2c61d51d961ff7d1bb89cd8d57b6dffe1c9e78570aae-primary.sqlite.bz2: [Errno 12] Timeout on http://hk.mirrors.thegigabit.com/epel/7/x86_64/repodata/256fe13c9b4274f5ab2b2c61d51d961ff7d1bb89cd8d57b6dffe1c9e78570aae-primary.sqlite.bz2: (28, 'Operation too slow. Less than 1000 bytes/sec transferred the last 30 seconds') 正在尝试其它镜像。 epel/x86_64/primary_db FAILED ETA http://my.mirrors.thegigabit.com/epel/7/x86_64/repodata/256fe13c9b4274f5ab2b2c61d51d961ff7d1bb89cd8d57b6dffe1c9e78570aae-primary.sqlite.bz2: [Errno 12] Timeout on http://my.mirrors.thegigabit.com/epel/7/x86_64/repodata/256fe13c9b4274f5ab2b2c61d51d961ff7d1bb89cd8d57b6dffe1c9e78570aae-primary.sqlite.bz2: (28, 'Operation too slow. Less than 1000 bytes/sec transferred the last 30 seconds') 正在尝试其它镜像。 epel/x86_64/primary_db | 6.9 MB 00:00:21 软件包 bridge-utils-1.5-9.el7.x86_64 已安装并且是最新版本 无须任何处理

二、将eth0绑到br0下

1.更改以太网配置文件，如图中所示。

[root@centos3 ~]# cd /etc/sysconfig/network-scripts/ [root@centos3 network-scripts]# ls ifcfg-ens33 ifdown-isdn ifup ifup-plip ifup-tunnel ifcfg-lo ifdown-post ifup-aliases ifup-plusb ifup-wireless ifdown ifdown-ppp ifup-bnep ifup-post init.ipv6-global ifdown-bnep ifdown-routes ifup-eth ifup-ppp network-functions ifdown-eth ifdown-sit ifup-ib ifup-routes network-functions-ipv6 ifdown-ib ifdown-Team ifup-ippp ifup-sit ifdown-ippp ifdown-TeamPort ifup-ipv6 ifup-Team ifdown-ipv6 ifdown-tunnel ifup-isdn ifup-TeamPort [root@centos3 network-scripts]# vim ifcfg-ens33

2.创建br0

[root@centos3 network-scripts]# vim ifcfg-br0

①配置格式如下图，内容需按照自身的ip地址。

②重启网络：

[root@azhan network-scripts]# service network restart Restarting network (via systemctl): [ 确定 ] [root@azhan network-scripts]#

三.查看网络设备

会发现多了个br0

[root@azhan network-scripts]# ifconfig br0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.8.121 netmask 255.255.255.0 broadcast 192.168.8.255 inet6 fe80::20c:29ff:fe7a:e32e prefixlen 64 scopeid 0x20<link> ether 00:0c:29:7a:e3:2e txqueuelen 1000 (Ethernet) RX packets 90 bytes 13749 (13.4 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 70 bytes 7852 (7.6 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 ether 00:0c:29:7a:e3:2e txqueuelen 1000 (Ethernet) RX packets 1513 bytes 1779200 (1.6 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 520 bytes 43526 (42.5 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1000 (Local Loopback) RX packets 32 bytes 2592 (2.5 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 32 bytes 2592 (2.5 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 virbr0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500 inet 192.168.122.1 netmask 255.255.255.0 broadcast 192.168.122.255 ether 52:54:00:66:07:be txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

四.检验是否通网

[root@azhan ~]# ping baidu.com PING baidu.com (220.181.38.148) 56(84) bytes of data. 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=1 ttl=128 time=79.9 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=2 ttl=128 time=91.1 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=3 ttl=128 time=77.8 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=4 ttl=128 time=81.1 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=5 ttl=128 time=89.1 ms 64 bytes from 220.181.38.148 (220.181.38.148): icmp_seq=6 ttl=128 time=91.6 ms