一、lvs+keepalived高可用集群部署
案例需求
部署基于LVS DR模式的web高可用集群,实现:
- 实现数据服务器容错
 - 实现分发器故障切换
 - 任何机器宕机不中断web业务
 
实验环境
六台安装Linux的虚拟机一台测试机,两台LVS分发器,一台路由器,两台web服务器,关闭selinux关闭防火墙,停止libvirtd.service服务
| 角色名称 | 接口名称 | IP地址 | 
|---|---|---|
| client | ens33 | 192.168.1.200 | 
| route | ens33,ens160 | 192.168.1.1,192.168.2.1 | 
| lvs1 | ens33 | 192.168.2.200,192.168.2.100(VIP) | 
| lvs2 | ens33 | 192.168.2.150,192.168.2.100(VIP) | 
| rs1 | ens33,lo:0 | 192.168.2.220,192.168.2.100(VIP) | 
| rs2 | ens33,lo:0 | 192.168.2.210,192.168.2.100(VIP) | 
实验拓扑图

实验步骤
a、配置客户端
ens33=192.168.1.200
[root@client ~]# route add default gw 192.168.1.1
b、设置路由
ens33=192.168.1.1
ens160=192.168.2.1
[root@route ~]# echo 1 > /proc/sys/net/ipv4/ip_forward
c、设置RS的VIP、网关、内核参数
RS1
[root@rs1 ~]# route add default gw 192.168.2.1
[root@rs1 ~]# ifconfig lo:0 192.168.2.100 netmask 255.255.255.255 up
[root@rs1 ~]# echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore 
[root@rs1 ~]# echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce 
RS2
[root@rs2 ~]# route add default gw 192.168.2.1
[root@rs2 ~]# ifconfig lo:0 192.168.2.100 netmask 255.255.255.255 up
[root@rs2 ~]# echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore 
[root@rs2 ~]# echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce 
安装web服务,生成测试页面
RS1
[root@rs1 ~]# apt install apache2 -y
[root@rs1 ~]# echo "rs1" > /var/www/html/index.html
[root@rs1 ~]# systemctl start httpd.service
RS2
[root@rs2 ~]# apt install apache2 -y
[root@rs2 ~]# echo "rs2" > /var/www/html/index.html
[root@rs2 ~]# systemctl start httpd.service
d、设置LVS
### LVS1 安装软件包,修改配置文件
[root@lvs1 ~]# apt install ipvsadm keepalived -y
[root@lvs1 ~]# vim /etc/keepalived/keepalived.conf 
! Configuration File for keepalived
global_defs {
   router_id lvs_1
}
vrrp_instance apache {
    state MASTER
    interface ens33
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.2.100/24
    }
}
virtual_server 192.168.2.100 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    nat_mask 255.255.255.0
#    persistence_timeout 50
    protocol TCP
    real_server 192.168.2.210 80 {
        weight 1
        TCP_CHECK {
              connect_timeout 3
              connect_port 80
            }
        }
    real_server 192.168.2.220 80 {
        weight 1
        TCP_CHECK {
              connect_timeout 3
              connect_port 80
            }
        }
}
### 重启keepalived服务
[root@lvs1 ~]# systemctl start keepalived.service 
### 使用ip add命令查看所设置的VIP是否被设置
[root@lvs1 ~]# ip add
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:6d:1c:b3 brd ff:ff:ff:ff:ff:ff
    inet 192.168.2.200/24 brd 192.168.2.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet 192.168.2.100/24 scope global secondary ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::474:99dd:c899:455f/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
### LVS2    安装软件包,修改配置文件
[root@lvs2 ~]# apt install ipvsadm keepalived -y
[root@lvs2 ~]# vim /etc/keepalived/keepalived.conf 
! Configuration File for keepalived
global_defs {
   router_id lvs_1
}
vrrp_instance apache {
    state BACKUP
    interface ens33
    virtual_router_id 51
    priority 10
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.2.100/24
    }
}
virtual_server 192.168.2.100 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    nat_mask 255.255.255.0
#    persistence_timeout 50
    protocol TCP
    real_server 192.168.2.210 80 {
        weight 1
        TCP_CHECK {
              connect_timeout 3
              connect_port 80
            }
        }
    real_server 192.168.2.220 80 {
        weight 1
        TCP_CHECK {
              connect_timeout 3
              connect_port 80
            }
        }
}
### 重启keepalived服务
[root@lvs2 ~]# systemctl start keepalived.service
e、客户端测试
### 客户端验证分发
[root@client ~]# apt install elinks -y
[root@client ~]# elinks http://192.168.2.100 --dump
   rs1
[root@client ~]# elinks http://192.168.2.100 --dump
   rs2
### 停止lvs1的keepalived服务  验证分发器故障切换
[root@lvs1 ~]# systemctl stop keepalived.service 
使用ip add命令查看VIP是否被释放
[root@lvs1 ~]# ip add
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:6d:1c:b3 brd ff:ff:ff:ff:ff:ff
    inet 192.168.2.200/24 brd 192.168.2.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::474:99dd:c899:455f/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
切换到lvs2查看VIP是否被设置
[root@lvs2 ~]# ip add
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:5c:a0:66 brd ff:ff:ff:ff:ff:ff
    inet 192.168.2.150/24 brd 192.168.2.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet 192.168.2.100/24 scope global secondary ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::5726:cbb9:c37b:d898/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
切换到客户端测试
[root@client ~]# elinks http://192.168.2.100 --dump
   rs1
[root@client ~]# elinks http://192.168.2.100 --dump
   rs2
### 停止RS1数据服务器查看数据服务器容错
[root@rs1 ~]#  systemctl stop httpd
切换到客户端测试:用户只能访问到RS1的页面
[root@client ~]# elinks http://192.168.2.100 --dump
   rs1
[root@client ~]# elinks http://192.168.2.100 --dump
   rs1
提示:使用tcpdump命令可以看到vrrp的相关信息发送信息,深度理解VRRP协议
[root@lvs1 ~]# tcpdump -nn -vvv vrrp