keepalived双主以及nginx+keepalived实现高可用

一、keepalive实现双主:
1.1实验准备
2台主机地址分别为:172.20.10.9,172.20.10.10,
vip1为172.20.10.10，vip2为172.20.10.11
1.2通知脚本:

[root@node5 /]# vim /etc/keepalived/notify.sh #!/bin/bashcontact='root@localhost'notify() {    local mailsubject="$(hostname) to be $1, vip floating"    local mailbody="$(date +'%F %T'): vrrp transition, $(hostname) changed to be $1"    echo "$mailbody" | mail -s "$mailsubject" $contact}case $1 inmaster)    notify master    ;;backup)     notify backup    ;;   fault)        notify fault    ;;  *)   echo "Usage: $(basename $0) {master|backup|fault}"   exit 1   ;;esac

1.3配置node5为vip1地址的主节点，vip2地址的备节点

[root@node5 ~]# vim /etc/keepalived/keepalived.conf! Configuration File for keepalivedglobal_defs {   notification_email {      root@localhost   }   notification_email_from keepalived@localhost   smtp_server 127.0.0.1   smtp_connect_timeout 30   router_id node5   vrrp_mcast_group4 224.0.100.19}vrrp_instance VI_1 {    state MASTER    interface ens33    virtual_router_id 51    priority 100    advert_int 1    authentication {        auth_type PASS        auth_pass 1111    }    virtual_ipaddress {        172.20.10.10/28 dev ens33 label ens33:0    }   notify_master "/etc/keepalived/notify.sh master"   notify_backup "/etc/keepalived/notify.sh backup"   notify_fault "/etc/keepalived/notify.sh fault"}vrrp_instance VI_2 {    state BACKUP    interface ens33    virtual_router_id 52    priority 98    advert_int 1    authentication {        auth_type PASS        auth_pass 1111    }    virtual_ipaddress {        172.20.10.11/28 dev ens33 label ens33:1    }   notify_master "/etc/keepalived/notify.sh master"   notify_backup "/etc/keepalived/notify.sh backup"   notify_fault "/etc/keepalived/notify.sh fault"}

1.4配置node6为vip1地址的备节点，vip2地址的主节点

[root@node6 ~]# vim /etc/keepalived/keepalived.conf ! Configuration File for keepalivedglobal_defs {   notification_email {      root@localhost   }   notification_email_from keepalived@localhost   smtp_server 127.0.0.1   smtp_connect_timeout 30   router_id node5   vrrp_mcast_group4 224.0.100.19}vrrp_instance VI_1 {    state BACKUP    interface ens33    virtual_router_id 51    priority 98    advert_int 1    authentication {        auth_type PASS        auth_pass 1111    }    virtual_ipaddress {        172.20.10.10/28 dev ens33 label ens33:0    }   notify_master "/etc/keepalived/notify.sh master"   notify_backup "/etc/keepalived/notify.sh backup"   notify_fault "/etc/keepalived/notify.sh fault"}vrrp_instance VI_2 {    state MASTER    interface ens33    virtual_router_id 52    priority 100    advert_int 1    authentication {        auth_type PASS        auth_pass 1111    }    virtual_ipaddress {        172.20.10.11/28 dev ens33 label ens33:1    }   notify_master "/etc/keepalived/notify.sh master"   notify_backup "/etc/keepalived/notify.sh backup"   notify_fault "/etc/keepalived/notify.sh fault"}

1.5验证:
(1)先开启node6节点的keepalived服务,查看IP地址，状态:
2个VIP地址都在node6节点上：

(2)再开启node5节点keepalived服务,查看IP地址和状态:
VIP1地址已经飘到了node5节点上了


二，Nginx+Keepalived实现站点高可用
2.1实验准备:
2台主机:node5地址为172.20.10.9，node6的节点为172.20.10.8
vip地址为172.20.10.10
2.2nginx配置
(1)node5节点

[root@node5 ~]# yum install nginx -y[root@node5 /]# vim /usr/share/nginx/html/index.html node5 web page[root@node5 ~]# systemctl  start nginx

(2)node6节点

[root@node6 /]# yum install -y  nginx[root@node6 /]# vim /usr/share/nginx/html/index.html node6 web page[root@node6 ~]# systemctl  start nginx

2.3配置node5为vip的主节点，配置检查nginx的监控脚本:

[root@node5 /]# vim /etc/keepalived/keepalived.conf! Configuration File for keepalivedglobal_defs {   notification_email {      root@localhost   }   notification_email_from keepalived@localhost   smtp_server 127.0.0.1   smtp_connect_timeout 30   router_id node5   vrrp_mcast_group4 224.0.100.19}vrrp_script chk_nginx {    script "/usr/bin/killall -0 nginx &&  exit 0 || exit 1 "    interval 1    weight -5    fall 2    rise 1}vrrp_instance VI_1 {    state MASTER    interface ens33    virtual_router_id 51    priority 100    advert_int 1    authentication {        auth_type PASS        auth_pass 1111    }    virtual_ipaddress {        172.20.10.10/28 dev ens33 label ens33:0    }    track_script {        chk_nginx    }    track_interface {        ens33    }   notify_master "/etc/keepalived/notify.sh master"   notify_backup "/etc/keepalived/notify.sh backup"   notify_fault "/etc/keepalived/notify.sh fault"}[root@node5 keepalived]# systemctl  start   keepalived

2.4配置node6为vip的备节点，配置检查nginx的监控脚本:

[root@node6 /]# vim /etc/keepalived/keepalived.conf ! Configuration File for keepalivedglobal_defs {   notification_email {      root@localhost   }   notification_email_from keepalived@localhost   smtp_server 127.0.0.1   smtp_connect_timeout 30   router_id node5   vrrp_mcast_group4 224.0.100.19}vrrp_script chk_nginx {    script "/usr/bin/killall -0 nginx &&  exit 0 || exit 1 "    interval 1    weight -5    fall 2    rise 1}vrrp_instance VI_1 {    state BACKUP    interface ens33    virtual_router_id 51    priority 98    advert_int 1    authentication {        auth_type PASS        auth_pass 1111    }    virtual_ipaddress {        172.20.10.10/28 dev ens33 label ens33:0    }    track_script {        chk_nginx    }    track_interface {        ens33    }   notify_master "/etc/keepalived/notify.sh master"   notify_backup "/etc/keepalived/notify.sh backup"   notify_fault "/etc/keepalived/notify.sh fault"}[root@node6 html]# systemctl  start   keepalived

3.验证：
3.1当服务都正常时，vip地址在node5节点上,测试访问172.20.10.10的情况:


3.2当down掉node5节点上nginx服务时，观察vip地址和其访问情况:
vip地址飘到node6节点上，curl172.20.10.10，则访问的时node6节点

3.3当恢复node5节点上nginx服务时，vip地址飘到node5节点上，访问172.20.10.10则是node5上nginx