HA Cluste 的配置：keepalived:vrrp协议 双主模型

keepalived:vrrp协议 双主模型

   第一步配置出始环境：
        准备两节点：
            主节点:172.18.57.7 long1
            备节点:172.18.57.8 long2
    (1) 各节点时间必须同步；      
        同步时间：
            ~]# yum -y install chrony
            ~]# vim /etc/chrony.conf
            ~]# systemctl start chronyd
            ~]# chronyc sources
            ~]# chronyc sourcestats
    (2) 确保iptables及selinux不会成为阻碍；       
        清空防火墙：
            ~]# iptables -F
        关闭SELinux
            ~]# setenforce 0
        清空规则：
            ~]# ipvsadm -C
        重新启动网络：
            ~]#systemctl restart network    
    (3) 各节点之间可通过主机名互相通信（对KA并非必须）；
        修改域名解析使用/etc/hosts文件实现；
             ~]#vim /etc/hosts
                172.18.57.7 long1
                172.18.57.8 long2
    第二步：keepalived安装
        long1 ~]#yum -y install keepalived
        long2 ~]#yum -y install keepalived

   第三步：修改配置文件
        [root@long1 ~]# vim /etc/keepalived/keepalived.conf
            ! Configuration File for keepalived

            global_defs {
               notification_email {
                root@localhost
               }

               notification_email_from keepalived@localhost
               smtp_server 127.0.0.1
               smtp_connect_timeout 30
               router_id long1
               vrrp_mcast_group4 224.0.101.57
            }

            vrrp_instance myr1 {
                state MASTER
                interface ens33
                virtual_router_id 57
                priority 100
                advert_int 1
                authentication {
                    auth_type PASS
                    auth_pass dAcLuTSt
                }
                virtual_ipaddress {
                    172.18.57.57/16 dev ens33
                }
            }
            vrrp_instance myr2 {
                state BACKUP
                interface ens33
                virtual_router_id 58
                priority 98
                advert_int 1
                authentication {
                    auth_type PASS
                    auth_pass dAcLUTSt
                }
                virtual_ipaddress {
                    172.18.57.157/16 dev ens33
                }
            }
        [root@long2 ~]#vim /etc/keepalived/keepalived.conf
            ! Configuration File for keepalived

            global_defs {
               notification_email {
                root@localhost
               }

               notification_email_from keepalived@localhost
               smtp_server 127.0.0.1
               smtp_connect_timeout 30
               router_id long2
               vrrp_mcast_group4 224.0.101.57
            }

            vrrp_instance myr1 {
                state BACKUP
                interface ens33
                virtual_router_id 57
                priority 98
                advert_int 1
                authentication {
                    auth_type PASS
                    auth_pass dAcLuTSt
                }
                virtual_ipaddress {
                    172.18.57.57/16 dev ens33
                }
            }
            vrrp_instance myr2 {
                state MASTER
                interface ens33
                virtual_router_id 157
                priority 100
                advert_int 1
                authentication {
                    auth_type PASS
                    auth_pass dAcLUTSt
                }
                virtual_ipaddress {
                    172.18.57.157/16 dev ens33
                }
            }

   第四步：启动服务，查看状态
        [root@long1 ~]#systemctl start keepalived.service
        [root@long2 ~]#systemctl start keepalived.service
        [root@long1 ~]# systemctl status keepalived.service
        [root@long2 ~]# systemctl status keepalived.service
        [root@long1 ~]# tcpdump -i ens33 host 224.0.101.57

   模拟宕机long1：
        [root@long1 ~]# iptables -A OUTPUT -s 172.18.57.7 -d 224.0.101.57 -j REJECT
        [root@long1 ~]# systemctl status keepalived.service
        [root@long1 ~]# iptables -F

   实验节点ip发生转移是发送邮件：通知脚本
        [root@long1 ~]#systemctl stop keepalived
        [root@long2 ~]#systemctl stop keepalived
        [root@long1 ~]# vim /etc/keepalived/notify.sh
            #!/bin/bash
            #
            contact='root@localhost'

            notify () {
                    mailsubject="vrrp:$(hostname) to be $1"
                    mailbody="$(hostname) to be $1, vrrp transition,$(date)."
                    echo "$mailbody" | mail -s "$mailsubject" $contact
            }

            case $1 in
            master)
                    notify master ;;
            backup)
                    notify backup ;;
            fault)
                    notify fault ;;
            *)
                    echo "Usage: $(basename $0) master|backup|fault"
                    exit 1 
                    ;;
            esac
        [root@long1 ~]# chmod +x notify.sh
        [root@long1 ~]# vim /etc/keepalived/keepalived.conf
            notify_master "/etc/keepalived/notify.sh master"
            notify_backup "/etc/keepalived/notify.sh backup"
            notify_fault "/etc/keepalived/notify.sh fault"  
        [root@long2 ~]# vim /etc/keepalived/notify.sh
            #!/bin/bsah
            #
            contact='root@localhost'

            notify () {
                    mailsubject="vrrp:$(hostname) to be $1"
                    mailbody="$(hostname) to be $1, vrrp transition,$(date)."
                    echo "$mailbody" | mail -s "$mailsubject" $contact
            }

            case $1 in
            master)
                    notify master ;;
            backup)
                    notify backup ;;
            fault)
                    notify fault ;;
            *)
                    echo "Usage: $(basename $0) master|backup|fault"
                    exit 1 
                    ;;
            esac
        [root@long2 ~]# vim /etc/keepalived/keepalived.conf
            notify_master "/etc/keepalived/notify.sh master"
            notify_backup "/etc/keepalived/notify.sh backup"
            notify_fault "/etc/keepalived/notify.sh fault"
        [root@long2 ~]#systemctl start keepalived
        [root@long2 ~]#mail
        [root@long2 keepalived]#mail
            Heirloom Mail version 12.5 7/5/10.  Type ? for help.
            "/var/spool/mail/root": 2 messages 1 new 2 unread
            >N  1 root  Sun May 14 20:53  19/684   "vrrp: long2 to be backup"
             N  2 root  Sun May 14 20:53  18/674   "vrrp: long2 to be master"
        [root@long1 ~]#systemctl start keepalived
        [root@long1 ~]#mail
            Heirloom Mail version 12.5 7/5/10.  Type ? for help.
            "/var/spool/mail/root": 2 messages 2 new
            >N  1 root  Sun May 14 20:53  18/674   "vrrp: long1 to be backup"
             N  2 root  Sun May 14 20:53  18/674   "vrrp: long1 to be master"
        [root@long2 ~]#mail
            Heirloom Mail version 12.5 7/5/10.  Type ? for help.
            "/var/spool/mail/root": 3 messages 1 new 3 unread
             U  1 root   Sun May 14 20:53  19/684   "vrrp: long2 to be backup"
             U  2 root   Sun May 14 20:53  19/684   "vrrp: long2 to be master"
            >N  3 root   Sun May 14 20:54  18/674   "vrrp: long2 to be backup"