使用LVS实现多服务复杂化均衡

实验结构图：

 

系统环境：

VMWare ESXi

CentOS 5.2

Apache

qmail

LVS 实现方式: DR

DR 是指 Direct Routing ，它的转发流程是： Director 机器收到外界请求，按相应的调度算法将其直接发送到相应 Real Server ， Real Server 处理完该请求后，将结果数据包直接返回给客户，完成一次负载调度。

需要的软件包： ipvsadm-1.24-8.1

网络配置：

LD Server eth0 10.0.10.209

Real Server1 eth0 10.0.10.207

Real Server2 eth0 10.0.10.208

Real Server3 eth0 10.0.10.210

Real Server4 eth0 10.0.10.240

VIP 10.0.10.60

VIP2 10.0.10.61

 

用户请求 http 连接是指向 10.0.10.60 ， LD Server 通过权重轮询（ wrr ）调度，将 http 请求转发到 Real Server 群中。

LVS 的配置是通过前面所安装的 IP 虚拟服务器软件 ipvsadm 来实现的。 ipvsadm 与 LVS 的关系类似于 iptables 和 NetFilter 的关系，前者只是一个建立和修改规则的工具，这些命令的作用在系统重新启动后就消失了，所以应该将这些命令写到一个脚本里，然后让它在系统启动后自动执行。

 

LD Server 启动脚本：/etc/init.d/lvsDR

#!/bin/sh
#
# description: start LVS of Director Server    
# created in 2009-04-29 by Dika.Ye

VIP=10.0.10.60
VIP2=10.0.10.61
RIP1=10.0.10.207
RIP2=10.0.10.208
RIP3=10.0.10.210
RIP4=10.0.10.240
#RIP3=10.0.10.x

GW=10.0.10.254

SER_PORT=80
SMTP_PORT=25
HTTP_CON_INTERFACE=eth0:6721
SMTP_CON_INTERFACE=eth0:6725
ATTEM=wrr

# Source function library.
. /etc/rc.d/init.d/functions

case $1 in
        start)
                echo -n "Starting LVS of Director Server "    
                #Set the Virtual IP Address    
                /sbin/ifconfig $HTTP_CON_INTERFACE $VIP broadcast $VIP netmask 255.255.255.255 up
                /sbin/ifconfig $SMTP_CON_INTERFACE $VIP2 broadcast $VIP2 netmask 255.255.255.255 up
                /sbin/route add -host $VIP dev $HTTP_CON_INTERFACE
                /sbin/route add -host $VIP2 dev $SMTP_CON_INTERFACE
                #Clear IPVS Table    
                /sbin/ipvsadm -C
                #Set Lvs for http
                /sbin/ipvsadm -A -t $VIP:$SER_PORT -s $ATTEM
                /sbin/ipvsadm -a -t $VIP:$SER_PORT -r $RIP1:$SER_PORT -g
                #Set LVS for smtp
                /sbin/ipvsadm -A -t $VIP2:$SMTP_PORT -s $ATTEM
                /sbin/ipvsadm -a -t $VIP2:$SMTP_PORT -r $RIP3:$SMTP_PORT -g
                /sbin/ipvsadm -a -t $VIP2:$SMTP_PORT -r $RIP4:$SMTP_PORT -g
                #Run Lvs    
                /sbin/ipvsadm
                echo "."
                ;;
        stop)
                echo -n "Close LVS Director Server "    
                /sbin/ifconfig $HTTP_CON_INTERFACE down
                /sbin/ifconfig $SMTP_CON_INTERFACE down
                /sbin/ipvsadm -C
                echo "."
                ;;
        status)
                echo "IPVSADM list"
                ipvsadm -Ln
                ;;
        *)
                echo "Usage: $0" {start|stop}    
                exit 1
esac

 

Real Server启动脚本：/etc/init.d/lvsRS

HTTP Real Server

 

#!/bin/sh
# decription:start realserver    
# chkconfig 235 26 26    

VIP=10.0.10.60
VIP2=10.0.10.61
RIP1=10.0.10.207
RIP2=10.0.10.208
RIP3=10.0.10.210
RIP4=10.0.10.240
#RIP3=10.0.10.x

GW=10.0.10.254

SER_PORT=80
SMTP_PORT=25
HTTP_CON_INTERFACE=lo:6721
SMTP_CON_INTERFACE=lo:6725
ATTEM=wrr

. /etc/rc.d/init.d/functions

case "$1" in
                start)
                echo " start LVS of REALServer"    
                /sbin/ifconfig $HTTP_CON_INTERFACE $VIP broadcast $VIP netmask 255.255.255.255 up
                /sbin/route add -host $VIP dev $HTTP_CON_INTERFACE
                echo "0" > /proc/sys/net/ipv4/ip_forward
                echo "1" >/proc/sys/net/ipv4/conf/lo/arp_ignore
                echo "2" >/proc/sys/net/ipv4/conf/lo/arp_announce
                echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore
                echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce
                ;;
                stop)
                /sbin/ifconfig $HTTP_CON_INTERFACE down
                echo " stop LVS service"    
                echo "0" >/proc/sys/net/ipv4/conf/lo/arp_ignore
                echo "0" >/proc/sys/net/ipv4/conf/lo/arp_announce
                echo "0" >/proc/sys/net/ipv4/conf/all/arp_ignore
                echo "0" >/proc/sys/net/ipv4/conf/all/arp_announce
                ;;
                *)
                echo "Usage: $0 {start|stop}"    
                exit 1
esac

 

Real Server启动脚本：/etc/init.d/lvsRS

SMTP Real Server

 

#!/bin/sh
# decription:start realserver    
# chkconfig 235 26 26    

VIP=10.0.10.60
VIP2=10.0.10.61
RIP1=10.0.10.207
RIP2=10.0.10.208
RIP3=10.0.10.210
RIP4=10.0.10.240
#RIP3=10.0.10.x

GW=10.0.10.254

SER_PORT=80
SMTP_PORT=25
HTTP_CON_INTERFACE=lo:6721
SMTP_CON_INTERFACE=lo:6725
ATTEM=wrr

. /etc/rc.d/init.d/functions

case "$1" in
                start)
                echo " start LVS of REALServer"    
                /sbin/ifconfig $SMTP_CON_INTERFACE $VIP2 broadcast $VIP2 netmask 255.255.255.255 up
                /sbin/route add -host $VIP2 dev $SMTP_CON_INTERFACE
                echo "0" > /proc/sys/net/ipv4/ip_forward
                echo "1" >/proc/sys/net/ipv4/conf/lo/arp_ignore
                echo "2" >/proc/sys/net/ipv4/conf/lo/arp_announce
                echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore
                echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce
                ;;
                stop)
                /sbin/ifconfig $SMTP_CON_INTERFACE down
                echo " stop LVS service"    
                echo "0" >/proc/sys/net/ipv4/conf/lo/arp_ignore
                echo "0" >/proc/sys/net/ipv4/conf/lo/arp_announce
                echo "0" >/proc/sys/net/ipv4/conf/all/arp_ignore
                echo "0" >/proc/sys/net/ipv4/conf/all/arp_announce
                ;;
                *)
                echo "Usage: $0 {start|stop}"    
                exit 1
esac

 

 

启动服务：

 

LD Server

 

# service lvsDR start

 

Real Server

 

# service lvsRS start