基于Keepalived实现LVS双主高可用集群

 

1、环境准备

设备	IP地址	作用	系统版本
Keepalived-Lvs	192.168.100.118	Keepalived-Lvs负载冗余	Rocky8.6
Keepalived-Lvs	192.168.100.123	Keepalived-Lvs负载冗余	Rocky8.6
Nginx	192.168.100.110	Nginx-Web反向代理+web	Rocky8.6
Nginx	192.168.100.114	Nginx-Web反向代理+web	Rocky8.6
client	192.168.100.250	测试	Rocky8.6

1-1、时间同步

 #所有节点时间同步：
 [root@node118 ~]# yum -y install chrony
 [root@node118 ~]# systemctl enable --now chronyd
 [root@node118 ~]# chronyc sources

1-2、基于主机名互相通信

 # 两个节点步骤相同：
 [root@node118 ~]# vim /etc/hosts
 192.168.100.118 node118.wang.org
 192.168.100.123 node123.wang.org
 ​
 [root@node118 ~]# vim /etc/hostname
 node118.wang.org

1-3、打通SSH互信

 [root@node118 ~]# ssh-keygen
 [root@node118 ~]# ssh-copy-id node123.wang.org
 ​
 [root@node123 ~]# ssh-keygen
 [root@node123 ~]# ssh-copy-id node118.wang.org
 ​

1-4、安装程序

 # 两个节点都需安装：
 [root@node118 ~]# yum install -y keepalived ipvsadm

2、配置keepalived

 [root@node118 ~]# vim /etc/keepalived/keepalived.conf 
 ! Configuration File for keepalived
 ​
 global_defs {
    notification_email {
      root@wang.org
    }
    notification_email_from root@wang.org
    smtp_server 127.0.0.1
    smtp_connect_timeout 30
    router_id node118
    vrrp_skip_check_adv_addr
   # vrrp_strict
    vrrp_garp_interval 0
    vrrp_gna_interval 0
   # vrrp_mcast_group4 224.0.0.18    #组播，如果开启组播，请把单播注释
 }
 ​
 vrrp_instance VI_1 {          #定义VRRP实例,实例名自定义
     state MASTER              #指定Keepalived的角色，MASTER为主服务器，BACKUP为备用服务器
     interface eth0            #指定HA监测的接口
     virtual_router_id 51      #虚拟路由标识(1-255)，在一个VRRP实例中主备服务器ID必须一样
     priority 100              #优先级，数字越大越优先，主服务器优先级必须高于备服务器
     advert_int 1              #设置主备之间同步检查时间间隔，单位秒
     authentication {          #设置验证类型和密码
         auth_type PASS        #验证类型
         auth_pass 1111        #设置验证密码，同一实例中主备密码要保持一致
     }
     virtual_ipaddress {       #定义虚拟IP地址
         192.168.200.88  dev eth0 label eth0:1
     }
     unicast_src_ip 192.168.100.118     #定义单播
     unicast_peer {
         192.168.100.123
     }
 }
 vrrp_instance VI_2 {
     state BACKUP                                                                              
     interface eth0
     virtual_router_id 61
     priority 80
     advert_int 1
     authentication {
         auth_type PASS
         auth_pass 2222
     }
     virtual_ipaddress {
         192.168.200.99 dev eth0 label eth0:2
     }
     unicast_src_ip 192.168.100.123
     unicast_peer {
         192.168.100.118
     }
 }
 virtual_server 192.168.200.88 80 {                                                            
     delay_loop 6
     lb_algo rr
     lb_kind DR
     nat_mask 255.255.255.0
     persistence_timeout 50
     protocol TCP
     sorry_server 127.0.0.1 80
     real_server 192.168.100.110 80 {
         weight 1
         HTTP_GET {
             url {
               path /
 #              digest 640205b7b0fc66c1ea91c463fac6334d
               status_code 200
             }
             connect_timeout 2
             retry 3
             delay_before_retry 1
         }
     }
     real_server 192.168.100.114 80 {
         weight 1
 #        HTTP_GET {
 #            url {
 #              path /
 #              digest 640205b7b0fc66c1ea91c463fac6334d
 #              status_code 200
 #            }
          TCP_CHECK {
             connect_timeout 2
             retry 3
             delay_before_retry 1
             connect_port 80
          }
         }
     }
 virtual_server 192.168.200.99 80 {                   
     delay_loop 6
     lb_algo rr
     lb_kind DR
     nat_mask 255.255.255.0
     persistence_timeout 50
     protocol TCP
     sorry_server 127.0.0.1 80
     real_server 192.168.100.110 80 {
         weight 1
         HTTP_GET {
             url {
               path /
 #              digest 640205b7b0fc66c1ea91c463fac6334d
               status_code 200
             }
             connect_timeout 2
             retry 3
             delay_before_retry 1
         }
     }
     real_server 192.168.100.114 80 {
         weight 1
 #        HTTP_GET {
 #            url {
 #              path /
 #              digest 640205b7b0fc66c1ea91c463fac6334d
 #              status_code 200
 #            }
          TCP_CHECK {
             connect_timeout 2
             retry 3
             delay_before_retry 1
             connect_port 80
          }
         }
     }
 ​
 ​

3、将配置文件复制给另一个节点

 [root@node118 ~]# scp /etc/keepalived/keepalived.conf node123.wang.org:/etc/keepalived/keepalived.conf 

4、另一个节点修改配置文件

 ​
 global_defs {
    notification_email {
      root@wang.org
    }
    notification_email_from root@wang.org
    smtp_server 127.0.0.1
    smtp_connect_timeout 30
    router_id node123                                                                          
    vrrp_skip_check_adv_addr
   # vrrp_strict
    vrrp_garp_interval 0
    vrrp_gna_interval 0
   # vrrp_mcast_group4 224.0.0.18
 }
 ​
 vrrp_instance VI_1 {
     state BACKUP
     interface eth0
     virtual_router_id 51
     priority 80
     advert_int 1
     authentication {
         auth_type PASS
         auth_pass 1111
     }
     virtual_ipaddress {
         192.168.200.88 dev eth0 label eth0:1
     }
     unicast_src_ip 192.168.100.123
     unicast_peer {
         192.168.100.118
 ​
     } 
 }
 vrrp_instance VI_2 {
     state MASTER
     interface eth0
     virtual_router_id 61
     priority 200
     advert_int 1
     authentication {
         auth_type PASS
         auth_pass 2222
     }
     virtual_ipaddress {
         192.168.200.99  dev eth0 label eth0:2
     }                                                                           unicast_src_ip 192.168.100.123
     unicast_peer {
         192.168.100.118
     }               
 }
 # 其他配置不变

5、后端服务器配置

 # 所有后端服务器节点执行：
 [root@node110 ~]# echo 1 > /proc/sys/net/ipv4/conf/eth0/arp_ignore 
 [root@node110 ~]# echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore 
 [root@node110 ~]# echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce 
 [root@node110 ~]# echo 2 > /proc/sys/net/ipv4/conf/eth0/arp_announce
 ​
 [root@node110 ~]# ifconfig lo:0 192.168.100.88 netmask 255.255.255.255 broadcast 192.168.100.88 up
 ​
 [root@node110 ~]# ifconfig lo:1 192.168.100.99 netmask 255.255.255.255 broadcast 192.168.100.99 up
 [root@node110 ~]# route add -host 192.168.100.88 dev lo:0
 [root@node110 ~]# route add -host 192.168.100.99 dev lo:1
 [root@node110 ~]# systemctl restart nginx.service

6、查看两节点的ip和ipvs规则情况

[root@node118 ~]# systemctl restart keepalived.service ;ssh node123.wang.org 'systemctl restart keepalived'       #启动keepalived
[root@node118 ~]# ip a s
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 52:54:00:d6:eb:f3 brd ff:ff:ff:ff:ff:ff
    inet 192.168.100.118/24 brd 192.168.100.255 scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
    inet 192.168.100.88/32 scope global eth0:1
       valid_lft forever preferred_lft forever
    inet6 fe80::5054:ff:fed6:ebf3/64 scope link 
       valid_lft forever preferred_lft forever
[root@node118 ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.100.88:80 rr
  -> 192.168.100.110:80           Route   1      0          0         
  -> 192.168.100.114:80           Route   1      0          0         
TCP  192.168.100.99:80 rr persistent 50
  -> 192.168.100.110:80           Route   1      0          0         
  -> 192.168.100.114:80           Route   1      0          0       
       
[root@node123 ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 52:54:00:02:b1:c5 brd ff:ff:ff:ff:ff:ff
    inet 192.168.100.123/24 brd 192.168.100.255 scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
    inet 192.168.100.99/32 scope global eth0:2
       valid_lft forever preferred_lft forever
    inet6 fe80::5054:ff:fe02:b1c5/64 scope link 
       valid_lft forever preferred_lft forever

[root@node123 ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.100.88:80 rr persistent 50
  -> 192.168.100.110:80           Route   1      0          0         
  -> 192.168.100.114:80           Route   1      0          0         
TCP  192.168.100.99:80 rr persistent 50
  -> 192.168.100.110:80           Route   1      0          0         
  -> 192.168.100.114:80           Route   1      0          0   

7、客户端测试

[root@wdy software]#while :;do curl 192.168.100.88;sleep 1;done
192.168.100.110
192.168.100.114
192.168.100.110
192.168.100.114
192.168.100.110
192.168.100.114
192.168.100.110
192.168.100.114
192.168.100.110