HA Cluste 的配置：keepalived:vrrp協議 雙主模型

keepalived:vrrp協議 雙主模型

   第一步配置出始環境：
        準備兩節點：
            主節點:172.18.57.7 long1
            備節點:172.18.57.8 long2
    (1) 各節點時間必須同步；      
        同步時間：
            ~]# yum -y install chrony
            ~]# vim /etc/chrony.conf
            ~]# systemctl start chronyd
            ~]# chronyc sources
            ~]# chronyc sourcestats
    (2) 確保iptables及selinux不會成為阻礙；       
        清空防火墻：
            ~]# iptables -F
        關閉SELinux
            ~]# setenforce 0
        清空規則：
            ~]# ipvsadm -C
        重新啟動網絡：
            ~]#systemctl restart network    
    (3) 各節點之間可通過主機名互相通信（對KA并非必須）；
        修改域名解析使用/etc/hosts文件實現；
             ~]#vim /etc/hosts
                172.18.57.7 long1
                172.18.57.8 long2
    第二步：keepalived安裝
        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：啟動服務，查看狀態
        [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

   模擬宕機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

   實驗節點ip發生轉移是發送郵件：通知腳本
        [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"