centos6.5网络虚拟化技术

一、配置KVM虚拟机NAT网络

 1、创建脚本执行权限

下面是NAT启动脚本

# vi /etc/qemu-ifup-NAT 

 赋予权限

# chmod +x /etc/qemu-ifup-NAT 

下载镜像文件

cirror project:为cliud环境测试vm提供的微缩版linux

镜像名称: cirros-0.3.4-x86_64-disk.img

镜像下载地址：http://download.cirros-cloud.net/0.3.4/

把镜像放到默认位置

# wget http://download.cirros-cloud.net/0.3.4/cirros-0.3.4-x86_64-disk.img

# mv cirros-0.3.4-x86_64-disk.img /var/lib/libvirt/images/

通过命令启动虚拟机

 # qemu-kvm -m 1024 -drive file=cirros-0.3.4-x86_64-disk.img,if=virtio -net nic,model=virtio -net tap,script=/etc/qemu-ifup-NAT -nographic -vnc :2 

实验失败，创建的虚拟机登录不进去，启动的时候报错

二、配置KVM虚拟机Bridge网络

1、安装工具

安装brctl和tunctl命令行工具

# yum install bridge-utils tunctl -y

查看tun模块是否加载

[root@localhost ~]# lsmod | grep tun
tun                    17095  2 vhost_net

2、创建Bridge

[root@localhost ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:2a:09:c7 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.55/24 brd 192.168.1.255 scope global eth0
inet6 fe80::20c:29ff:fe2a:9c7/64 scope link
valid_lft forever preferred_lft forever
3: virbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN
link/ether 52:54:00:dc:9c:cd brd ff:ff:ff:ff:ff:ff
inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN qlen 500
link/ether 52:54:00:dc:9c:cd brd ff:ff:ff:ff:ff:ff
[root@localhost ~]#
[root@localhost ~]#
[root@localhost ~]# brctl addbr br0
[root@localhost ~]#
[root@localhost ~]# brctl addif br0 eth0

 Xshell断开连接，在主机内部进行操作

网卡配置分别配置如下

[root@localhost ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0 
DEVICE=eth0
TYPE=Ethernet
ONBOOT=yes
NM_CONTROLLED=no
BOOTPROTO=none
DRIDGE=br0
[root@localhost ~]# 
[root@localhost ~]# cat /etc/sysconfig/network-scripts/ifcfg-br0 
DEVICE=br0
TYPE=bridge
ONBOOT=yes
NM_CONTROLLED=no
BOOTPROTO=static
IPADDR=192.168.1.55
NETMASK=255.255.255.0
GATEWAY=192.168.1.1
DNS1=8.8.8.8

 重启网卡配置生效

[root@localhost ~]# service network restart
Shutting down interface eth0:                              [  OK  ]
Shutting down loopback interface:                          [  OK  ]
Bringing up loopback interface:                            [  OK  ]
Bringing up interface br0:  Determining if ip address 192.168.1.55 is already in use for device br0...
                                                           [  OK  ]
Bringing up interface eth0:                                [  OK  ]

Xshell连接

查看网络信息

[root@localhost ~]# ip addr list
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:2a:09:c7 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::20c:29ff:fe2a:9c7/64 scope link 
       valid_lft forever preferred_lft forever
3: virbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN 
    link/ether 52:54:00:dc:9c:cd brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN qlen 500
    link/ether 52:54:00:dc:9c:cd brd ff:ff:ff:ff:ff:ff
6: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN 
    link/ether 00:0c:29:2a:09:c7 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.55/24 brd 192.168.1.255 scope global br0
    inet6 fe80::20c:29ff:fe2a:9c7/64 scope link 
       valid_lft forever preferred_lft forever

查看路由表

[root@localhost ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 br0
192.168.122.0   0.0.0.0         255.255.255.0   U     0      0        0 virbr0
169.254.0.0     0.0.0.0         255.255.0.0     U     1002   0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1006   0        0 br0
0.0.0.0         192.168.1.1     0.0.0.0         UG    0      0        0 br0

 查看桥接信息

[root@localhost ~]# brctl show
bridge name     bridge id               STP enabled     interfaces
br0             8000.000c292a09c7       no              eth0
virbr0          8000.525400dc9ccd       yes             virbr0-nic

 查看br0桥

[root@localhost ~]# brctl show br0
bridge name     bridge id               STP enabled     interfaces
br0             8000.000c292a09c7       no              eth0