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keepalived高可用

2022-10-09 08:32:15 作業系統

keepalived高可用

目錄
  • keepalived高可用
    • keepalived簡介
    • keepalived的重要功能
    • keepalived作業原理描述
    • keepalived實作nginx負載均衡機高可用
      • keepalived安裝
      • 在主備機上分別安裝nginx
      • keepalived配置
      • 查看VIP在哪里
      • 測驗
      • 讓keepalived監控nginx負載均衡機
      • 配置keepalived加入監控腳本的配置
      • 測驗

keepalived簡介

keepalived官網
Keepalived 軟體起初是專為LVS負載均衡軟體設計的，用來管理并監控LVS集群系統中各個服務節點的狀態，后來又加入了可以實作高可用的VRRP功能，因此，Keepalived除了能夠管理LVS軟體外，還可以作為其他服務（例如：Nginx、Haproxy、MySQL等）的高可用解決方案軟體，

Keepalived軟體主要是通過VRRP協議實作高可用功能的，VRRP是Virtual Router RedundancyProtocol(虛擬路由器冗余協議）的縮寫，VRRP出現的目的就是為了解決靜態路由單點故障問題的，它能夠保證當個別節點宕機時，整個網路可以不間斷地運行，

所以，Keepalived 一方面具有配置管理LVS的功能，同時還具有對LVS下面節點進行健康檢查的功能，另一方面也可實作系統網路服務的高可用功能，

keepalived的重要功能

eepalived 有三個重要的功能，分別是：

管理LVS負載均衡軟體
實作LVS集群節點的健康檢查
作為系統網路服務的高可用性（failover）

keepalived作業原理描述

Keepalived高可用對之間是通過VRRP通信的，因此，我們從 VRRP開始了解起：

  1. VRRP,全稱 Virtual Router Redundancy Protocol,中文名為虛擬路由冗余協議，VRRP的出現是為了解決靜態路由的單點故障，
  2. VRRP是通過一種竟選協議機制來將路由任務交給某臺 VRRP路由器的，
  3. VRRP用 IP多播的方式（默認多播地址（224.0_0.18))實作高可用對之間通信，
  4. 作業時主節點發包，備節點接包，當備節點接收不到主節點發的資料包的時候，就啟動接管程式接管主節點的開源，備節點可以有多個，通過優先級競選，但一般 Keepalived系統運維作業中都是一對，
  5. VRRP使用了加密協議加密資料，但Keepalived官方目前還是推薦用明文的方式配置認證型別和密碼，

介紹完 VRRP,接下來我再介紹一下 Keepalived服務的作業原理：

Keepalived高可用是通過 VRRP 進行通信的， VRRP是通過競選機制來確定主備的，主的優先級高于備，因此，作業時主會優先獲得所有的資源，備節點處于等待狀態，當主掛了的時候，備節點就會接管主節點的資源，然后頂替主節點對外提供服務，

在 Keepalived 服務之間，只有作為主的服務器會一直發送 VRRP 廣播包,告訴備它還活著，此時備不會槍占主，當主不可用時，即備監聽不到主發送的廣播包時，就會啟動相關服務接管資源，保證業務的連續性.接管速度最快可以小于1秒，

keepalived實作nginx負載均衡機高可用

環境說明:

系統資訊 主機名 IP
centos 8.5 master 192.168.222.138
centos 8.5 backup 192.168.222.139

本次高可用虛擬IP（VIP）地址暫定為192.168.222.133

keepalived安裝

阿里云官網
配置主keepalived

關閉防火墻:
[root@master ~]# systemctl stop firewalld.service 
[root@master ~]# vim /etc/selinux/config 
SELINUX=disabled
[root@master ~]# setenforce 0
[root@master ~]# systemctl disable --now firewalld.service 
Removed /etc/systemd/system/multi-user.target.wants/firewalld.service.
Removed /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
配置網路源:
[root@master ~]# dnf -y install wget
[root@master ~]# cd /etc/yum.repos.d/
[root@master yum.repos.d]# wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo
[root@master yum.repos.d]#sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo
安裝epel源:
[root@master yum.repos.d]#dnf install -y https://mirrors.aliyun.com/epel/epel-release-latest-8.noarch.rpm
[root@master yum.repos.d]#sed -i 's|^#baseurl=https://download.example/pub|baseurl=https://mirrors.aliyun.com|' /etc/yum.repos.d/epel*
[root@master yum.repos.d]#sed -i 's|^metalink|#metalink|' /etc/yum.repos.d/epel*
[root@master yum.repos.d]# ls
CentOS-Base.repo   epel-next-testing.repo  epel-playground.repo       epel-testing.repo
epel-modular.repo  epel-next.repo          epel-testing-modular.repo  epel.repo
查找keepalived:
[root@master yum.repos.d]# cd
[root@master ~]# dnf list all |grep keepalived
Failed to set locale, defaulting to C.UTF-8
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
keepalived.x86_64                                                 2.1.5-6.el8                                            AppStream   
安裝keepalived:
[root@master ~]# dnf -y install keepalived
查看組態檔:
[root@master ~]# ls /etc/keepalived/
keepalived.conf
查看安裝生成的檔案:
[root@master ~]# rpm -ql keepalived 
/etc/keepalived     //配置目錄
/etc/keepalived/keepalived.conf   //此為主組態檔
/etc/sysconfig/keepalived
/usr/bin/genhash
/usr/lib/.build-id
/usr/lib/.build-id/0a
/usr/lib/.build-id/0a/410997e11c666114ca6d785e58ff0cc248744e
/usr/lib/.build-id/6f
/usr/lib/.build-id/6f/ba0d6bad6cb5ff7b074e703849ed93bebf4a0f
/usr/lib/systemd/system/keepalived.service  //此為服務控制檔案
/usr/libexec/keepalived
/usr/sbin/keepalived
/usr/share/doc/keepalived
/usr/share/doc/keepalived/AUTHOR
/usr/share/doc/keepalived/CONTRIBUTORS
/usr/share/doc/keepalived/COPYING
/usr/share/doc/keepalived/ChangeLog
/usr/share/doc/keepalived/README
/usr/share/doc/keepalived/TODO
/usr/share/doc/keepalived/keepalived.conf.HTTP_GET.port
/usr/share/doc/keepalived/keepalived.conf.IPv6
/usr/share/doc/keepalived/keepalived.conf.PING_CHECK
/usr/share/doc/keepalived/keepalived.conf.SMTP_CHECK
/usr/share/doc/keepalived/keepalived.conf.SSL_GET
/usr/share/doc/keepalived/keepalived.conf.SYNOPSIS
/usr/share/doc/keepalived/keepalived.conf.UDP_CHECK
/usr/share/doc/keepalived/keepalived.conf.conditional_conf
/usr/share/doc/keepalived/keepalived.conf.fwmark
/usr/share/doc/keepalived/keepalived.conf.inhibit
/usr/share/doc/keepalived/keepalived.conf.misc_check
/usr/share/doc/keepalived/keepalived.conf.misc_check_arg
/usr/share/doc/keepalived/keepalived.conf.quorum
/usr/share/doc/keepalived/keepalived.conf.sample
/usr/share/doc/keepalived/keepalived.conf.status_code
/usr/share/doc/keepalived/keepalived.conf.track_interface
/usr/share/doc/keepalived/keepalived.conf.virtual_server_group
/usr/share/doc/keepalived/keepalived.conf.virtualhost
/usr/share/doc/keepalived/keepalived.conf.vrrp
/usr/share/doc/keepalived/keepalived.conf.vrrp.localcheck
/usr/share/doc/keepalived/keepalived.conf.vrrp.lvs_syncd
/usr/share/doc/keepalived/keepalived.conf.vrrp.routes
/usr/share/doc/keepalived/keepalived.conf.vrrp.rules
/usr/share/doc/keepalived/keepalived.conf.vrrp.scripts
/usr/share/doc/keepalived/keepalived.conf.vrrp.static_ipaddress
/usr/share/doc/keepalived/keepalived.conf.vrrp.sync
/usr/share/man/man1/genhash.1.gz
/usr/share/man/man5/keepalived.conf.5.gz
/usr/share/man/man8/keepalived.8.gz
/usr/share/snmp/mibs/KEEPALIVED-MIB.txt
/usr/share/snmp/mibs/VRRP-MIB.txt
/usr/share/snmp/mibs/VRRPv3-MIB.txt

用同樣的方法在備服務器上安裝keepalived

關閉防火墻:
[root@backup ~]# systemctl stop firewalld.service 
[root@backup ~]# vim /etc/selinux/config 
SELINUX=disabled
[root@backup ~]# setenforce 0
[root@backup ~]# systemctl disable --now firewalld.service 
Removed /etc/systemd/system/multi-user.target.wants/firewalld.service.
Removed /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
配置網路源:
[root@backup ~]# dnf -y install wget
[root@backup ~]# cd /etc/yum.repos.d/
[root@backup yum.repos.d]# wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo
[root@backup yum.repos.d]#sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo
安裝epel源
[root@backup yum.repos.d]#dnf install -y https://mirrors.aliyun.com/epel/epel-release-latest-8.noarch.rpm
[root@backup yum.repos.d]#sed -i 's|^#baseurl=https://download.example/pub|baseurl=https://mirrors.aliyun.com|' /etc/yum.repos.d/epel*
[root@backup yum.repos.d]#sed -i 's|^metalink|#metalink|' /etc/yum.repos.d/epel*
[root@backup yum.repos.d]# ls
CentOS-Base.repo   epel-next-testing.repo  epel-playground.repo       epel-testing.repo
epel-modular.repo  epel-next.repo          epel-testing-modular.repo  epel.repo
查找keepalived:
[root@backup yum.repos.d]# cd
[root@backup ~]# dnf list all |grep keepalived
Failed to set locale, defaulting to C.UTF-8
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
Module yaml error: Unexpected key in data: static_context [line 9 col 3]
keepalived.x86_64                                                 2.1.5-6.el8                                            AppStream   
安裝keepalived:
[root@backup ~]# dnf -y install keepalived
查看組態檔:
[root@backup ~]# ls /etc/keepalived/
keepalived.conf
查看安裝生成的檔案:
[root@backup ~]# rpm -ql keepalived 
/etc/keepalived     //配置目錄
/etc/keepalived/keepalived.conf   //此為主組態檔
/etc/sysconfig/keepalived
/usr/bin/genhash
/usr/lib/.build-id
/usr/lib/.build-id/0a
/usr/lib/.build-id/0a/410997e11c666114ca6d785e58ff0cc248744e
/usr/lib/.build-id/6f
/usr/lib/.build-id/6f/ba0d6bad6cb5ff7b074e703849ed93bebf4a0f
/usr/lib/systemd/system/keepalived.service  //此為服務控制檔案
/usr/libexec/keepalived
/usr/sbin/keepalived
/usr/share/doc/keepalived
/usr/share/doc/keepalived/AUTHOR
/usr/share/doc/keepalived/CONTRIBUTORS
/usr/share/doc/keepalived/COPYING
/usr/share/doc/keepalived/ChangeLog
/usr/share/doc/keepalived/README
/usr/share/doc/keepalived/TODO
/usr/share/doc/keepalived/keepalived.conf.HTTP_GET.port
/usr/share/doc/keepalived/keepalived.conf.IPv6
/usr/share/doc/keepalived/keepalived.conf.PING_CHECK
/usr/share/doc/keepalived/keepalived.conf.SMTP_CHECK
/usr/share/doc/keepalived/keepalived.conf.SSL_GET
/usr/share/doc/keepalived/keepalived.conf.SYNOPSIS
/usr/share/doc/keepalived/keepalived.conf.UDP_CHECK
/usr/share/doc/keepalived/keepalived.conf.conditional_conf
/usr/share/doc/keepalived/keepalived.conf.fwmark
/usr/share/doc/keepalived/keepalived.conf.inhibit
/usr/share/doc/keepalived/keepalived.conf.misc_check
/usr/share/doc/keepalived/keepalived.conf.misc_check_arg
/usr/share/doc/keepalived/keepalived.conf.quorum
/usr/share/doc/keepalived/keepalived.conf.sample
/usr/share/doc/keepalived/keepalived.conf.status_code
/usr/share/doc/keepalived/keepalived.conf.track_interface
/usr/share/doc/keepalived/keepalived.conf.virtual_server_group
/usr/share/doc/keepalived/keepalived.conf.virtualhost
/usr/share/doc/keepalived/keepalived.conf.vrrp
/usr/share/doc/keepalived/keepalived.conf.vrrp.localcheck
/usr/share/doc/keepalived/keepalived.conf.vrrp.lvs_syncd
/usr/share/doc/keepalived/keepalived.conf.vrrp.routes
/usr/share/doc/keepalived/keepalived.conf.vrrp.rules
/usr/share/doc/keepalived/keepalived.conf.vrrp.scripts
/usr/share/doc/keepalived/keepalived.conf.vrrp.static_ipaddress
/usr/share/doc/keepalived/keepalived.conf.vrrp.sync
/usr/share/man/man1/genhash.1.gz
/usr/share/man/man5/keepalived.conf.5.gz
/usr/share/man/man8/keepalived.8.gz
/usr/share/snmp/mibs/KEEPALIVED-MIB.txt
/usr/share/snmp/mibs/VRRP-MIB.txt
/usr/share/snmp/mibs/VRRPv3-MIB.txt

在主備機上分別安裝nginx

在master上安裝nginx

[root@master ~]# dnf -y install nginx
[root@master ~]# cd /usr/share/nginx/html/
[root@master html]# ls
404.html  50x.html  index.html  nginx-logo.png  poweredby.png
[root@master html]# echo 'master' > index.html
[root@master html]# systemctl start nginx
[root@master html]# ss -antl
State      Recv-Q     Send-Q          Local Address:Port           Peer Address:Port     Process     
LISTEN     0          128                   0.0.0.0:111                 0.0.0.0:*                    
LISTEN     0          128                   0.0.0.0:80                  0.0.0.0:*                    
LISTEN     0          32              192.168.122.1:53                  0.0.0.0:*                    
LISTEN     0          128                   0.0.0.0:22                  0.0.0.0:*                    
LISTEN     0          128                      [::]:111                    [::]:*                    
LISTEN     0          128                      [::]:80                     [::]:*                    
LISTEN     0          128                      [::]:22                     [::]:*                    
[root@master html]# systemctl enable nginx
Created symlink /etc/systemd/system/multi-user.target.wants/nginx.service → /usr/lib/systemd/system/nginx.service.
//在主節點這邊需要設定開機自啟

在backup上安裝nginx

[root@backup ~]# dnf -y install nginx
[root@backup ~]# cd /usr/share/nginx/html/
[root@backup html]# ls
404.html  50x.html  index.html  nginx-logo.png  poweredby.png
[root@backup html]# echo 'backup' > index.html
root@backup html]# systemctl start nginx
[root@backup html]# ss -antl
State      Recv-Q     Send-Q          Local Address:Port           Peer Address:Port     Process     
LISTEN     0          128                   0.0.0.0:22                  0.0.0.0:*                    
LISTEN     0          128                   0.0.0.0:80                  0.0.0.0:*                    
LISTEN     0          128                      [::]:22                     [::]:*                    
LISTEN     0          128                      [::]:80                     [::]:*                    
//在備節點這邊不需要設定開機自啟

在瀏覽器上訪問試試，確保master上的nginx服務能夠正常訪問

keepalived配置

配置主keepalived

[root@master html]# cd /etc/keepalived/
[root@master keepalived]# ls
keepalived.conf
[root@master keepalived]# mv keepalived.conf{,-bak}
[root@master keepalived]# ls
keepalived.conf-bak                 //備份一下組態檔
[root@master keepalived]# dnf -y install vim
[root@master keepalived]# vim keepalived.conf  //編輯一個新組態檔
[root@master keepalived]# cat keepalived.conf
! Configuration File for keepalived

global_defs {
   router_id lb01
}

vrrp_instance VI_1 {        //這里主備節點需要一致
    state BACKUP
    interface ens33      //網卡
    virtual_router_id 51
    priority 100     //這里比備節點的高
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass tushanbu   //密碼(可以隨機生成)
    }
    virtual_ipaddress {
        192.168.222.133    //高可用虛擬IP（VIP）地址
    }
}

virtual_server 192.168.222.133 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP

    real_server 192.168.222.138 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.222.139 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
[root@master keepalived]# ls
keepalived.conf  keepalived.conf-bak
[root@master keepalived]# systemctl enable --now keepalived
Created symlink /etc/systemd/system/multi-user.target.wants/keepalived.service → /usr/lib/systemd/system/keepalived.service.
[root@master keepalived]# 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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:f6:83:57 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.138/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet 192.168.222.133/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fef6:8357/64 scope link 
       valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:db:51:2f brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc fq_codel master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:db:51:2f brd ff:ff:ff:ff:ff:ff
//此時備節點的keepalived還沒有啟動
[root@master keepalived]# scp keepalived.conf 192.168.222.139:/etc/keepalived
The authenticity of host '192.168.222.139 (192.168.222.139)' can't be established.
ECDSA key fingerprint is SHA256:anVVbTlEIzA1E8rB7IbLzaf7t9oQjB0qFP6Dd/ijnJI.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added '192.168.222.139' (ECDSA) to the list of known hosts.
[email protected]'s password: 
keepalived.conf                                                    100%  875   905.2KB/s   00:00    
//將創建的這個組態檔傳到備節點上去，因為主,備節點的這個組態檔基本上都是一樣的只需要改一點點

配置備keepalived

[root@backup html]# cd /etc/keepalived/
[root@backup keepalived]# ls
keepalived.conf
[root@backup keepalived]# mv keepalived.conf{,-bak}
[root@backup keepalived]# ls
keepalived.conf-bak               //備份一下組態檔
[root@backup keepalived]# dnf -y install vim
[root@backup keepalived]# ls     //接收到主節點傳過來的組態檔
keepalived.conf  keepalived.conf-bak
[root@backup keepalived]# vim keepalived.conf    //進行修改一下
[root@backup keepalived]# cat keepalived.conf
! Configuration File for keepalived

global_defs {
   router_id lb02    
}

vrrp_instance VI_1 {       //這里主備節點需要一致
    state BACKUP
    interface ens33      //網卡
    virtual_router_id 51
    priority 90     //這里比主節點的小
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass tushanbu   //密碼(可以隨機生成)
    }
    virtual_ipaddress {
        192.168.222.133    //高可用虛擬IP（VIP）地址
    }
}

virtual_server 192.168.222.133 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP

    real_server 192.168.222.138 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.222.139 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
[root@backup keepalived]# systemctl enable --now keepalived
Created symlink /etc/systemd/system/multi-user.target.wants/keepalived.service → /usr/lib/systemd/system/keepalived.service.

查看VIP在哪里

在MASTER上查看

[root@master keepalived]# 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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:f6:83:57 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.138/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet 192.168.222.133/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fef6:8357/64 scope link 
       valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:db:51:2f brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc fq_codel master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:db:51:2f brd ff:ff:ff:ff:ff:ff
//主節點上面有vip

在BACKUP上查看

[root@backup keepalived]# 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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:31:af:f9 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.139/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe31:aff9/64 scope link 
       valid_lft forever preferred_lft forever
//備節點上面沒有vip

測驗

停掉master的keepalived服務，開啟backup的niginx和keepalived服務然后查看主權情況
master

[root@master keepalived]# systemctl stop keepalived.service

backup:

[root@backup keepalived]# systemctl start nginx.service
[root@backup keepalived]# systemctl start keepalived.service
[root@backup keepalived]# 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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:31:af:f9 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.139/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet 192.168.222.133/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe31:aff9/64 scope link 
       valid_lft forever preferred_lft forever


//此時可以看見backup是主
然后再開啟master的keepalived服務再查看主權情況
master

[root@master keepalived]# systemctl start keepalived.service 
[root@master keepalived]# 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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:f6:83:57 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.138/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet 192.168.222.133/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fef6:8357/64 scope link 
       valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:db:51:2f brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc fq_codel master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:db:51:2f brd ff:ff:ff:ff:ff:ff

backup

[root@backup keepalived]# systemctl stop nginx.service 
//此時測驗的時候backup上面的nginx是要進行關閉的
[root@backup keepalived]# ss -antl
State      Recv-Q     Send-Q          Local Address:Port           Peer Address:Port     Process     
LISTEN     0          128                   0.0.0.0:22                  0.0.0.0:*                    
LISTEN     0          128                      [::]:22                     [::]:*                    
[root@backup keepalived]# 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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:31:af:f9 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.139/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe31:aff9/64 scope link 
       valid_lft forever preferred_lft forever


//此時可以看見master還是主

讓keepalived監控nginx負載均衡機

keepalived通過腳本來監控nginx負載均衡機的狀態
在master上撰寫腳本

[root@master keepalived]# cd
[root@master ~]# mkdir /scripts
[root@master ~]# cd /scripts/
[root@master scripts]# vim check_nginx.sh
[root@master scripts]# cat check_nginx.sh
#!/bin/bash
nginx_status=$(ps -ef|grep -Ev "grep|$0"|grep '\bnginx\b'|wc -l)
if [ $nginx_status -lt 1 ];then
    systemctl stop keepalived
fi
[root@master scripts]# chmod +x check_nginx.sh 
[root@master scripts]# ll
total 4
-rwxr-xr-x. 1 root root 142 Oct  8 23:21 check_nginx.sh
[root@master scripts]# vim notify.sh
[root@master scripts]# cat notify.sh
#!/bin/bash
case "$1" in
    master)
        nginx_status=$(ps -ef|grep -Ev "grep|$0"|grep '\bnginx\b'|wc -l)
        if [ $nginx_status -lt 1 ];then
            systemctl start nginx
        fi
    ;;
    backup)
        nginx_status=$(ps -ef|grep -Ev "grep|$0"|grep '\bnginx\b'|wc -l)
        if [ $nginx_status -gt 0 ];then
            systemctl stop nginx
        fi
    ;;
    *)
        echo "Usage:$0 master|backup VIP"
    ;;
esac
[root@master scripts]# chmod +x notify.sh 
[root@master scripts]# ll
total 8
-rwxr-xr-x. 1 root root 142 Oct  8 23:21 check_nginx.sh
-rwxr-xr-x. 1 root root 383 Oct  8 23:31 notify.sh
[root@master scripts]# scp check_nginx.sh 192.168.222.139:/scripts/
[email protected]'s password: 
check_nginx.sh                                                     100%  142   113.6KB/s   00:00    
[root@master scripts]# scp notify.sh 192.168.222.139:/scripts/
[email protected]'s password: 
notify.sh                                                          100%  383   244.7KB/s   00:00    
//將這個腳本傳給備節點上提前創建好的目錄里面

在backup上撰寫腳本

[root@backup keepalived]# cd
[root@backup ~]# mkdir /scripts
[root@backup ~]# cd /scripts/
[root@backup scripts]# ll
total 8
-rwxr-xr-x. 1 root root 142 Oct  8 23:39 check_nginx.sh
-rwxr-xr-x. 1 root root 383 Oct  8 23:36 notify.sh

配置keepalived加入監控腳本的配置

配置主keepalived

[root@master scripts]# cd
[root@master ~]# vim /etc/keepalived/keepalived.conf
[root@master ~]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   router_id lb01
}

vrrp_script nginx_check {   //添加這一部分
    script "/scripts/check_nginx.sh"
    interval 5
    weight -20
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens33      
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass tushanbu
    }
    virtual_ipaddress {
        192.168.222.133
    }
    track_script {    //添加這一部分
        nginx_check
    }
    notify_master "/scripts/notify.sh master 192.168.222.133"   
    notify_backup "/scripts/notify.sh backup 192.168.222.133"
}

virtual_server 192.168.222.133 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP

    real_server 192.168.222.138 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.222.139 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
[root@master ~]# systemctl restart keepalived.service
[root@master ~]# systemctl restart nginx.service

配置備keepalived
backup無需檢測nginx是否正常，當升級為MASTER時啟動nginx，當降級為BACKUP時關閉

[root@backup scripts]# cd
[root@backup ~]# vim /etc/keepalived/keepalived.conf
[root@backup ~]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   router_id lb02
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens33      
    virtual_router_id 51
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass tushanbu
    }
    virtual_ipaddress {
        192.168.222.133
    }
    notify_master "/scripts/notify.sh master 192.168.222.133" //添加
    notify_backup "/scripts/notify.sh backup 192.168.222.133" //添加
}

virtual_server 192.168.222.133 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP

    real_server 192.168.222.138 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.222.139 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
[root@backup ~]# systemctl restart keepalived.service 
[root@backup ~]# systemctl restart nginx.service

測驗

正常狀態運行查看狀態

master:
[root@master ~]# 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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:f6:83:57 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.138/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet 192.168.222.133/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fef6:8357/64 scope link 
       valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:db:51:2f brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc fq_codel master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:db:51:2f brd ff:ff:ff:ff:ff:ff
[root@master ~]# curl 192.168.222.133
master
backup:
[root@backup ~]# 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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:31:af:f9 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.139/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe31:aff9/64 scope link 
       valid_lft forever preferred_lft forever
停止nginx
[root@master ~]# systemctl stop nginx.service 
[root@master ~]# ss -antl
State      Recv-Q     Send-Q          Local Address:Port           Peer Address:Port     Process     
LISTEN     0          128                   0.0.0.0:111                 0.0.0.0:*                    
LISTEN     0          32              192.168.122.1:53                  0.0.0.0:*                    
LISTEN     0          128                   0.0.0.0:22                  0.0.0.0:*                    
LISTEN     0          128                      [::]:111                    [::]:*                    
LISTEN     0          128                      [::]:22                     [::]:*

master上停止nginx后的狀態

master：
[root@master ~]# 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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:f6:83:57 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.138/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fef6:8357/64 scope link 
       valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:db:51:2f brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc fq_codel master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:db:51:2f brd ff:ff:ff:ff:ff:ff
backup:
[root@backup ~]# 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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:31:af:f9 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.139/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet 192.168.222.133/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe31:aff9/64 scope link 
       valid_lft forever preferred_lft forever
[root@backup ~]# curl 192.168.222.133
backup

轉載請註明出處，本文鏈接：https://www.uj5u.com/caozuo/511106.html

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