++++++++++++
              +Client + eth0 192.168.1.1/24
            ++++++++++++
                ｜
                |

                ++++++++++++ up eth0 192.168.1.254/24
    |----------> +    GW +
    |         ++++++++++++ down eth1 1.1.1.254/24
    |             ｜
    |             |
    |         ++++++++++++ VIP eth0:1 1.1.1.1/24
    |         + Director +
    |         ++++++++++++ DIP eth0 1.1.1.100/24
    |                 |
    |__________________|_______________
        |                             |
        |                             |
    ++++++++++++             ++++++++++++
    + Real Server A +     + Real Server B +
    ++++++++++++             ++++++++++++
    eth0 1.1.1.10/24         eth0 1.1.1.20/24

1、数据包走向

1.Client---------->GW
sip:CIP         dip:VIP
smac:Client_mac dmac:GW_up_mac

2.GW-------------->Director
sip:CIP          dip:VIP
smac:GW_down_mac dmac:VIP_mac

3.Director-------->Real Server
******************************************************************
*    Director在给Real Server发包前要广播找Real Server mac    *
*    sip:    DIP sip:    RIP    *
*    smac:    DIP_mac dmac:    broadcast    *
*    *
*    sip:    RIP dip:    DIP    *
*    smac:    RealServer_mac    dmac:    DIP_mac    *
******************************************************************
sip:CIP        dip:VIP
smac:DIP_mac   dmac:RealServer_mac

4.Real Server----->GW
sip:VIP              dip:CIP
smac:RealServer_mac  dmac:GW_down_mac

5.GW-------------->Client
sip:VIP        dip:CIP
smac:GW_up_mac dmac:Client_mac

2、配置LVS VS/NAT模式

Client:

[root@localhost ~]# route add default gw 192.168.1.254 dev eth0

GW:

[root@localhost ~]# echo 1 > /proc/sys/net/ipv4/ip_forward

Real Server A & Real Server B:

[root@localhost ~]# yum install httpd
[root@localhost ~]# ifconfig lo:1 1.1.1.1/32
[root@localhost ~]# echo 1 > /proc/sys/net/ipv4/conf/eth0/arp_ignore
[root@localhost ~]# echo 2 > /proc/sys/net/ipv4/conf/eth0/arp_announce

Director:

[root@localhost ~]# yum install ipvsadm
[root@localhost ~]# ipvsadm -A -t 1.1.1.1:80 -s rr
[root@localhost ~]# ipvsadm -a -t 1.1.1.1:80 -r 1.1.1.10:80 -g
[root@localhost ~]# ipvsadm -a -t 1.1.1.1:80 -r 1.1.1.20:80 -g
[root@localhost ~]# ipvsadm -Ln
[root@localhost ~]# ipvsadm -Ln --stats