1. 配置网络结构：
192.168.1.11和192.168.1.12是互为备份的LVS Director, 192.168.1.11默认为MASTER， 192.168.1.12为BACKUP
192.168.1.99是LVS Director的虚拟IP，当192.168.1.11正常工作时，它会通过VRRPv2协议向广播网段发送ARP数据包，声明192.168.1.99为其所有，当192.168.1.11宕机时，192.168.1.12会立即接管该工作，声明192.168.1.99的所有权并响应用户请求
192.168.1.13和192.168.1.14是 Real Server, 上面有监听在80端的Web 服务
2. Keepalived主机安装配置
1. 在192.168.1.11和192.168.1.12上安装keepalived, 安装完成后修改配置文件/etc/keepalived/keepalived.conf。
# yum install keepalived -y# vi /etc/keepalived/keepalived.conf
详细配置参数说明请参见官方文档：http://www.keepalived.org/doc/configuration_synopsis.html
2. 配置MASTER节点(192.168.1.11)，配置文件内容如下。关键配置内容添加了注释：
!ConfigurationFileforkeepalivedglobal_defs{router_idLVS_11#节点ID，每个节点的值唯一vrrp_skip_check_adv_addrvrrp_strict#严格遵守VRRP，三种情况将会阻止keepalived (1.无VIPs, 2.unicast peers,3.IPv6 addresses in VRRP version 2)vrrp_garp_interval0vrrp_gna_interval0}vrrp_instanceVI_1{#定义一个实例(高可用集群）stateMASTER#节点在Keepalived中定义为MASTERinterfaceenp0s3#指定节点发送ARP数据报时使用的网关设备virtual_router_id51#Virtual Router ID, 数字格式，集群中的所有节点值要相同，priority101#节点优先级，MASTER节点要比其它节点的值大advert_int1authentication{auth_typePASS#节点间的认证方式，支持PASS, HEADauth_passkeepsync#auth_type为PASS时的主证密码，超过8位则keepalived只取前8位}virtual_ipaddress{192.168.1.99#配置虚拟IP}}--------------------------------------分割线，如果只配置Keepalived主备集群，上面的配置就可以了，下面的配置用于配置LVS--------------------------------virtual_server192.168.1.9980{#配置LVS集群服务地址及端口delay_loop6lb_algolc#LVS请求分配算法，当前为LC，详见LVS文档lb_kindDR#LVS工作模式为DRpersistence_timeout50protocolTCP#LVS服务协议为TCPreal_server192.168.1.1380{#Real Server 1 地址及端口weight1#Real Server 1权重TCP_CHECK{#Real Server健康诊断方式为TCP_CHECK, 支持的方式有TCP_CHECK, HTTP_GET, SSL_GET, MISC_CHECKconnect_timeout3#诊断间隔为3秒connect_port80#诊断连接端口为80}}real_server192.168.1.1480{#Real Server 1 配置weight1TCP_CHECK{connect_timeout3connect_port80}}}
3. 配置BACKUP节点(192.168.1.12)：
!ConfigurationFileforkeepalivedglobal_defs{router_idLVS_12#每个节点唯一，与其它节点不周vrrp_skip_check_adv_addrvrrp_strictvrrp_garp_interval0vrrp_gna_interval0}vrrp_instanceVI_1{stateBACKUP#指定为BACKUP模式interfaceenp0s3virtual_router_id51#与其它节点相同priority100#优先级比MASTER低advert_int1authentication{auth_typePASSauth_passkeepsync}virtual_ipaddress{192.168.1.99}}virtual_server192.168.1.9980{delay_loop6lb_algolclb_kindDRpersistence_timeout50protocolTCPreal_server192.168.1.1380{weight1TCP_CHECK{connect_timeout3connect_port80nb_get_retry3delay_before_retry3}}real_server192.168.1.1480{weight1TCP_CHECK{connect_timeout3connect_port80}}}
Keepalived会按TCP_CHECK中配置的connect_timeout时间间隔尝试连接real server的connect_port指定的端口，如果指定server的指定端口不可达，该real server会被从LVS集群中移除，待该server恢复后又会被自动加入到集群。
关于Health Check的详细信息请参见：http://www.keepalived.org/doc/software_design.html#healthcheck-framework
4. 在MASTER和BACKUP节点上启动并启用keepalived服务：
# systemctl start keepalived#systemctlenablekeepalived
如果Keepalived MASTER节点上安装了ipvsadm管理工具，可以看到LVS配置已经生成：
[root@centos01~]#ipvsadm-LnIPVirtualServerversion1.2.1(size=4096)ProtLocalAddress:PortSchedulerFlags->RemoteAddress:PortForwardWeightActiveConnInActConnTCP192.168.1.99:80lcpersistent50->192.168.1.13:80Route100->192.168.1.14:80Route106
5. 在MASTER和BACKUP节点上启用ip_forward：
# cat<< EOF >/etc/sysctl.d/zz-keepalived.confnet.ipv4.ip_forward =1EOF# sysctl --system
/etc/sysctl.d目录下, 文件名排序越靠后，优先级越高, 所以以zz-..作为文件名前缀
3. Real Server配置
配置两台nginx服务器
新建lvs-web.sh
#!/bin/bash
VIP=192.168.1.99
case "$1" in
start)
echo "start LVS of RealServer DR"
/sbin/ifconfig lo:0 $VIP broadcast $VIP netmask 255.255.255.255 up
/sbin/route add -host $VIP dev lo:0
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 lo:0 down
echo "close LVS of RealServer DR"
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
exit 0
然后运行
测试,
就可以看到两台nginx会按照轮询的来访问了。
这样就表示成功
