宿主机为Centos6.3 64位，三台虚拟机为为Centos6.3 64位。虚拟机的网络连接方式为默认的NAT方式。虚拟机默认为DHCP方式动态获取IP。为了在三台虚拟机上搭建hadoop,需要将这三台虚拟机构建成可以相互访问的局域网，所以将三台虚拟机都设置成静态IP。具体设置方法如下：

1、在宿主机上执行：ifconfig -a

显示：
eth0      Link encap:Ethernet  HWaddr 00:0B:2F:XX:XX:XX 
          inet addr:XXX.XXX.XXX.XXX  Bcast:XXX.XXX.XXX.255  Mask:255.255.255.128
          inet6 addr: XXXXXXXXXXXXXXXXXX/64 Scope:Global
          inet6 addr: XXXXXXXXXX/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:335991 errors:0 dropped:0 overruns:0 frame:0
          TX packets:19935 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:54399176 (51.8 MiB)  TX bytes:2590997 (2.4 MiB)

eth1      Link encap:Ethernet  HWaddr 3F:3F:3F:3F:3F:3F  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

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:41128 errors:0 dropped:0 overruns:0 frame:0
          TX packets:41128 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:138218445 (131.8 MiB)  TX bytes:138218445 (131.8 MiB)

virbr0    Link encap:Ethernet  HWaddr 52:54:00:75:98:B4  
          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:1319 errors:0 dropped:0 overruns:0 frame:0
          TX packets:539 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:99958 (97.6 KiB)  TX bytes:453583 (442.9 KiB)

virbr0-nic Link encap:Ethernet  HWaddr 52:54:00:75:98:B4  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:500
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

vnet0     Link encap:Ethernet  HWaddr FE:54:00:17:67:42  
          inet6 addr: fe80::fc54:ff:fe17:6742/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:904 errors:0 dropped:0 overruns:0 frame:0
          TX packets:4557 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:500
          RX bytes:76846 (75.0 KiB)  TX bytes:472213 (461.1 KiB)

vnet1     Link encap:Ethernet  HWaddr FE:54:00:4B:93:57  
          inet6 addr: fe80::fc54:ff:fe4b:9357/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1443 errors:0 dropped:0 overruns:0 frame:0
          TX packets:5320 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:500
          RX bytes:132821 (129.7 KiB)  TX bytes:547440 (534.6 KiB)

vnet2     Link encap:Ethernet  HWaddr FE:54:00:05:B1:D6  
          inet6 addr: fe80::fc54:ff:fe05:b1d6/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1120 errors:0 dropped:0 overruns:0 frame:0
          TX packets:5152 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:500
          RX bytes:115229 (112.5 KiB)  TX bytes:327311 (319.6 KiB)

2、先在各虚拟机的终端命令窗口中执行：ifconfig -a

显示结果中会有eth0, eth1, 或eth2之类，以及HWaddr

3、执行：vim /etc/sysconfig/network-scripts/ifcfg-eth0(或ifcfg-eth1，ifcfg-eth2取决于第二步骤看到的结果)

编辑内容如下：

DEVICE=“eth1” #(或eth0,eth2取决于第二步骤看到的结果)

HWADDR="52:54:00:75:98:B4"#即第二步骤所得到的HWaddr值

ONBOOT="yes"

BOOTPROTO="static"

IPADDR=“192.168.122.10”#

NETMASK=“255.255.255.0”

GATEWAY=“192.168.122.1”#(取决于第1步中得到的virbr0     inet addr:192.168.122.1 ）

TYPE=“Ethernet”

至此，三台虚拟机之间以及与宿主机之间已经可以相互访问了，可以使用ping+IP来测试一下。

4、让各虚拟机可以上网。