Lvs+Keepalived高可用负载均衡配置
环境介绍：
vip=192.168.3.80 (负载均衡虚拟ip)
lvs+keepalived_master eth0:172.20.27.81 eth1:192.168.3.81 (1核1G)
lvs+keepalived_back eth0:172.20.27.82 eth1:192.168.3.82 (1核1G)
web01 eth0:172.20.27.83 eth1:192.168.3.83 (1核1G)
web02 eth0:172.20.27.84 eth1:192.168.3.84 (1核1G)
一、在(lvs主备节点)安装
1.安装依赖包：
yuminstall-ygccgcc-c++makepcrepcre-develkernel-developenssl-devellibnl-develpopt-develpopt-staticmodprobe-l|grepipvs//检查linux内核是否集成lvs模块：echo"1">/proc/sys/net/ipv4/ip_forward//开启路由转发功能：
2.安装ipvsadm
wget/software/kernel-2.6/ipvsadm-1.26.tar.gztarzxvfipvsadm-1.26.tar.gzcdipvsadm-1.26make&&makeinstall
3.安装keepalived
3.1安装配置keepalived
wget/software/keepalived-1.2.15.tar.gztarzxvfkeepalived-1.2.15.tar.gzcdkeepalived-1.2.15./configure--prefix=/usr/local/keepalivedmake&&makeinstall
3.2将keepalived配置成系统服务
cp/usr/local/keepalived/etc/rc.d/init.d/keepalived/etc/init.d/cp/usr/local/keepalived/etc/sysconfig/keepalived/etc/sysconfig/mkdir/etc/keepalived/cp/usr/local/keepalived/etc/keepalived/keepalived.conf/etc/keepalived/cp/usr/local/keepalived/sbin/keepalived/usr/sbin/
3.3修改keepalived配置文件
3.3.1修改lvs+keepalived_master的keepalived配置文件
echo''>/etc/keepalived/keepalived.conf//清空配置文件，自己写vim/etc/keepalived/keepalived.conf
!ConfigurationFileforkeepalivedglobal_defs{notification_email{331095659@#故障接受联系人}notification_email_from331095659@#故障发送人smtp_server127.0.0.1#本机发送邮件smtp_connect_timeout30router_idLVS_MASTER#lvs+keepalived_back上修改为LVS_BACKUP}vrrp_instanceVI_1{stateMASTER#lvs+keepalived_back上修改为BACKUPinterfaceeth1virtual_router_id51#虚拟路由标识，主从相同priority100#lvs+keepalived_back上修改为90advert_int1authentication{auth_typePASSauth_pass1111#主从认证密码必须一致}virtual_ipaddress{#Web虚拟IP（VTP）192.168.3.80}}virtual_server192.168.3.8080{#定义虚拟IP和端口delay_loop6#检查真实服务器时间，单位秒lb_algowlc#设置负载调度算法，wlc为加权最少链接（WeightedLeastConnections）比较多lb_kindDR#设置LVS负载均衡DR模式persistence_timeout60#同一IP的连接60秒内被分配到同一台真实服务器protocolTCP#使用TCP协议检查realserver状态real_server192.168.3.8380{#第一个web服务器weight3#节点权重值TCP_CHECK{#健康检查方式connect_timeout3#连接超时nb_get_retry3#重试次数delay_before_retry3#重试间隔/S}}real_server192.168.3.8480{#第二个web服务器weight3TCP_CHECK{connect_timeout3nb_get_retry3delay_before_retry3}}}
3.3.2修改lvs+keepalived_back的keepalived配置文件
echo''>/etc/keepalived/keepalived.conf//清空配置文件，自己写vim/etc/keepalived/keepalived.conf
!ConfigurationFileforkeepalivedglobal_defs{notification_email{331095659@}notification_email_from331095659@smtp_server127.0.0.1smtp_connect_timeout30router_idLVS_BACKUP}vrrp_instanceVI_1{stateBACKUPinterfaceeth1virtual_router_id51priority90advert_int1authentication{auth_typePASSauth_pass1111}virtual_ipaddress192.168.3.80}}virtual_server192.168.3.8080{delay_loop6lb_algowlclb_kindDRpersistence_timeout60protocolTCPreal_server192.168.3.8380{weight3TCP_CHECK{connect_timeout3nb_get_retry3delay_before_retry3}}real_server192.168.3.8480{weight3TCP_CHECK{connect_timeout3nb_get_retry3delay_before_retry3}}}
3.4 启动keepalived(lvs主备节点都启动)
servicekeepalivedrestartecho'servicekeepalivedstart'>>/etc/rc.local
二、分别在两台Web(web01和web02)服务器编写脚本并启动
vim/etc/init.d/real.sh#!/bin/bash#description:startrealserverVIP=192.168.3.80//keepalived虚拟ip./etc/init.d/functionscase"$1"instart)/sbin/ifconfiglo:0$VIPbroadcast$VIPnetmask255.255.255.255upecho"1">/proc/sys/net/ipv4/conf/lo/arp_ignoreecho"2">/proc/sys/net/ipv4/conf/lo/arp_announceecho"1">/proc/sys/net/ipv4/conf/all/arp_ignoreecho"2">/proc/sys/net/ipv4/conf/all/arp_announceecho"LVSRealServerStartOK";;stop)/sbin/ifconfiglo:0downecho"0">/proc/sys/net/ipv4/conf/lo/arp_ignoreecho"0">/proc/sys/net/ipv4/conf/lo/arp_announceecho"0">/proc/sys/net/ipv4/conf/all/arp_ignoreecho"0">/proc/sys/net/ipv4/conf/all/arp_announceecho"LVSRealServerStopedOK";;*)echo"Usage:$0{start|stop}"exit1esac
chmod+x/etc/init.d/real.sh/etc/init.d/real.shstartecho"/etc/init.d/real.shstart">>/etc/rc.local
三、测试及常用命令
常用命令：
ipvsadm-ln#显示集群中服务器ip信息ipaddr#显示VTP绑定在哪个服务器上tail-f/var/log/messger(从日志中可知，主机出现故障后，备机立刻检测到，此时备机变为MASTER角色，并且接管了主机的虚拟IP资源，最后将虚拟IP绑定在eth1设备上)
