linux中keepalived实现nginx高可用配置

linux中keepalived实现nginx高可用配置

安装keepalived

运行如下命令即可
tar -zxvf keepalived-2.0.8.tar.gz -C /usr/src
cd /usr/src/keepalived-2.0.8
sudo apt-get install autoconf
aclocal
autoconf
autoheader
automake --add-missing
sudo apt-get install libssl-dev
./configure --prefix=/usr/local/keepalived
make && make install
cd /usr/local/keepalived/sbin
./keepalived
ps -ef | grep keepalived

修改keepalived配置文件

keepalived的作用，基本上是和多台nginx服务器通信，当主服务器宕机，将ip分法给备用服务器
例如，写类似如下代码
    在你的linux网卡中添加一个ip地址，这个ip地址可以ping通，也就是多个nginx服务器，可以共用这一个ip，通过keepalived决定谁可以拥有这个ip
    ip addr add yourtestip dev ens33
    ip addr
    ping yourtestip
配置keepalived配置文件
sudo vim /usr/local/keepalived/etc/keepalived/keepalived.conf
    ! Configuration File for keepalived
    global_defs {
        # 服务器宕机发送通知邮件
        notification_email {
            acassen@firewall.loc
        }
        notification_email_from Alexandre.Cassen@firewall.loc
        smtp_server 192.168.200.1
        smtp_connect_timeout 30
        router_id LVS_DEVEL
        vrrp_skip_check_adv_addr
        vrrp_strict
        vrrp_garp_interval 0
        vrrp_gna_interval 0
    }
    # 虚拟路由器配置
    vrrp_instance VI_1 {
        state MASTER                                # 设置当前nginx服务器为主节点，备用nginx服务器对应设置成BACKUP即可
        interface eth0                              # 绑定服务器网卡
        virtual_router_id 51                        # 主备nginx服务器此id必须一致
        priority 100                                # 设置优先级，1-254之间，备用服务器的结点优先级设置低点
        advert_int 1                                # 信息发送间隔，主备都要一致
        authentication {                            # 授权信息，主备服务器一致
            auth_type PASS
            auth_pass 1111
        }
        virtual_ipaddress {                         # 虚拟IP，主备服务器必须一致，网段必须和nginx一致
            192.168.200.16
        }
        notify_master "/usr/local/keepalived/sbin/notify_sh master"  # 主服务器宕机，备用服务器要成为主服务器则调用此脚本
        notify_backup "/usr/local/keepalived/sbin/notify_sh backup"
        notify_fault "/usr/local/keepalived/sbin/notify_sh fault"
    }
    vrrp_script chk_health {
        script "[[`ps -ef | grep nginx | grep -v grep | wc -l`-ge 2]] && exit 0 || exit 1"          # 判断nginx进程是否大于等于2
        interval 1          # 1秒钟执行一次
        weight -2           # nginx宕机，本机权重降低2
    }
    track_script {
        chk_health          # 检查nginx
    }
notify_sh脚本
    #!/bin/bash
    case $1 in
        master)
            /usr/local/nginx/sbin/nginx
            exit 0
            ;;
        backup)
            /usr/local/nginx/sbin/nginx -s stop
            /usr/local/nginx/sbin/nginx
            exit 0
            ;;
        fault)
            /usr/local/nginx/sbin/nginx -s stop
            exit 0
        *)
            echo "(notify.sh(master|backup|fault)"
            exit 1
        ;;
    esac