CentOS6.3 KVM如何设置网卡为桥接模式


KVM的默认网络模式为NAT,就是说借助宿主机模式上网,现在我们想改成桥接模式,这样外界就可以直接和宿主机里的虚拟机通讯了,本文将介绍此方法的实现

KVM的默认网络模式为NAT,就是说借助宿主机模式上网,现在我们想改成桥接模式,这样外界就可以直接和宿主机里的虚拟机通讯了。

1,首先看一下默认的网络设置

复制代码代码如下:

# cat /etc/libvirt/qemu/networks/default.xml
default
1f118032-0345-4725-adcf-6b94f6aca19c

2,再看一下虚拟机配置文件里面的网络设置

#cat /etc/libvirt/qemu/ubuntu10.04.xml
ubuntu10.04
2eeb1395-39a2-a169-4da3-f22b20a1d34f
1048576
1048576
1
hvm
destroy
restart
restart
/usr/libexec/qemu-kvm



原来是interface type='default'

原来是source network='default',这里的br1要根据你的物理网卡下面有讲



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3,改完之后要更新一下配置文件

# virsh define ubuntu10.04.xml

定义域 ubuntu10.04(从 ubuntu10.04.xml)

#然后就可以virsh start ubuntu10.04了,不过现在物理网卡这块还没有改好

4,物理网卡可以手动更改,不过现在有现成的工具包,可以用这个更改

#wget http://www.convirture.com/downloads/convirture-tools/2.0.1/convirture-tools-2.0.1.tar.gz
# tar zxvf convirture-tools-2.0.1.tar.gz
# /root/convirture-tools/install/managed_server/scripts/convirt-tool --bridge setup

我的这里出现了点小问题,发现网络没起来,所以不要远程来做这个操作,主要原因是里面的配置文件有点需要

小的更改,我的是UUID注释了。

# ls ifcfg-*
ifcfg-br1 ifcfg-br2 ifcfg-br3 ifcfg-br4 ifcfg-em1 ifcfg-em2 ifcfg-em3 ifcfg-em4 ifcfg-lo

我这里有四个物理网卡,所以生成了四个bridge,不过真实用的只有br1

这个工具好有一个好处就是保存了原配置文件,如果你不想用时还可以还原

# ls saved.ifcfg-em*
saved.ifcfg-em1.20121128.101114 saved.ifcfg-em3.20121128.101114
saved.ifcfg-em2.20121128.101114 saved.ifcfg-em4.20121128.101114

看下ifceg-em1

# cat ifcfg-em1
DEVICE="em1"
#BOOTPROTO=none
NM_CONTROLLED="yes"
ONBOOT=yes
TYPE="Ethernet"
#UUID="3bc7fdcc-42b1-4223-b202-e697305897c8"
#IPADDR172.16.10.81
PREFIX=24
GATEWAY=172.16.10.254
DNS1=172.16.10.5
DEFROUTE=yes
IPV4_FAILURE_FATAL=yes
IPV6INIT=no
NAME="System em1"
HWADDR=90:B1:1C:20:4D:A5
BRIDGE=br1
看下ifcfg-br1
# cat ifcfg-br1
DEVICE="br1"
BOOTPROTO=none
NM_CONTROLLED="yes"
ONBOOT=yes
#UUID="3bc7fdcc-42b1-4223-b202-e697305897c8"
IPADDR=172.16.10.81
PREFIX=24
GATEWAY=172.16.10.254
DNS1=172.16.10.5
DEFROUTE=yes
IPV4_FAILURE_FATAL=yes
IPV6INIT=no
NAME="System br1"
TYPE=Bridge

最后看下网卡

# ifconfig
br1 Link encap:Ethernet HWaddr 90:B1:1C:20:4D:A5
inet addr:172.16.10.81 Bcast:172.16.10.255 Mask:255.255.255.0
inet6 addr: fe80::92b1:1cff:fe20:4da5/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:10219 errors:0 dropped:0 overruns:0 frame:0
TX packets:3776 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:576031 (562.5 KiB) TX bytes:15928008 (15.1 MiB)
em1 Link encap:Ethernet HWaddr 90:B1:1C:20:4D:A5
inet6 addr: fe80::92b1:1cff:fe20:4da5/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:10362 errors:0 dropped:0 overruns:0 frame:0
TX packets:13131 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:766684 (748.7 KiB) TX bytes:16489098 (15.7 MiB)
Interrupt:35
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:144411 errors:0 dropped:0 overruns:0 frame:0
TX packets:144411 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:147381248 (140.5 MiB) TX bytes:147381248 (140.5 MiB)
virbr0 Link encap:Ethernet HWaddr 52:54:00:F1:6B:6E
inet addr:192.168.122.1 Bcast:192.168.122.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2028 errors:0 dropped:0 overruns:0 frame:0
TX packets:1135 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:233311 (227.8 KiB) TX bytes:89372 (87.2 KiB)
vnet0 Link encap:Ethernet HWaddr FE:54:00:50:58:7E
inet6 addr: fe80::fc54:ff:fe50:587e/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:161 errors:0 dropped:0 overruns:0 frame:0
TX packets:3117 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:500
RX bytes:15533 (15.1 KiB) TX bytes:263947 (257.7 KiB)
vnet1 Link encap:Ethernet HWaddr FE:54:00:B5:1A:19
inet6 addr: fe80::fc54:ff:feb5:1a19/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:56 errors:0 dropped:0 overruns:0 frame:0
TX packets:794 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:500
RX bytes:8754 (8.5 KiB) TX bytes:42245 (41.2 KiB)

5,启动虚拟机ubuntu10.04后配置网卡

#cat /etc/network/interface
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet static
address 172.16.10.100
netmask 255.255.255.0
gateway 172.16.10.254
#/etc/init.d/networking restart

启动即可