Keepalive高可用部署

准备环境：两台机器，机器上提前装好nginx。

  • 第一种方法

  1. 安装keepalive，如无特殊要求，直接yum安装即可。

    # ct1
[root@ct1 ~]# yum install -y keepalived
# ct2
[root@ct2 ~]# yum install -y keepalived

  2. 配置文件

    # ct1 master 配置文件
! Configuration File for keepalived

global_defs {
   router_id LVS_DEVEL
}

vrrp_script check_nginx {
	script "/etc/keepalived/check_nginx.sh"
	interval 3
}

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 {
        192.168.174.100
    }

    track_script {
        check_nginx
    }

}


# ct2 backup配置文件
! Configuration File for keepalived

global_defs {
   router_id LVS_DEVEL
}

vrrp_script check_nginx {
	script "/etc/keepalived/check_nginx.sh"
	interval 3
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens33
    virtual_router_id 51
    priority 50
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.174.100
    }

    track_script {
        check_nginx
    }

}

    检测脚本：

    # check_nginx.sh		赋予执行权限
#! /bin/bash
num=`ps -ef |grep "nginx: master process" | grep -v "grep" | wc -l`
if [ $num -lt 1 ];then
    systemctl stop keepalived
fi

  3. 启动keepalive

    systemctl start keepalived

  4. 查看虚IP

    # ct1
[root@ct1 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:96:93:a5 brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.7/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 80398sec preferred_lft 80398sec
    inet 192.168.174.100/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
       
# ct2
[root@ct2 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:cc:c1:4a brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.8/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 80394sec preferred_lft 80394sec
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link tentative noprefixroute dadfailed 
       valid_lft forever preferred_lft forever
    inet6 fe80::8174:b896:90e9:17a3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

  5. 关闭ct1的nginx，测试虚IP切换，可以看到虚IP切换到了ct2上了。

    # ct1
[root@ct1 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:96:93:a5 brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.7/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 79911sec preferred_lft 79911sec
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
 
 # ct2
[root@ct2 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:cc:c1:4a brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.8/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 79909sec preferred_lft 79909sec
    inet 192.168.174.100/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link tentative noprefixroute dadfailed 
       valid_lft forever preferred_lft forever
    inet6 fe80::8174:b896:90e9:17a3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

  6. 恢复ct1服务，可以看到ct1恢复后，由于优先级高，虚IP又切换回来了

    # ct1
[root@ct1 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:96:93:a5 brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.7/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 79787sec preferred_lft 79787sec
    inet 192.168.174.100/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

# ct2
[root@ct2 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:cc:c1:4a brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.8/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 79784sec preferred_lft 79784sec
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link tentative noprefixroute dadfailed 
       valid_lft forever preferred_lft forever
    inet6 fe80::8174:b896:90e9:17a3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
  • 第二种方法
# ct1 配置文件
! Configuration File for keepalived

global_defs {
   router_id LVS_DEVEL
}

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 {
        192.168.174.100
    }

}

virtual_server 192.168.174.100 80 {		# 虚拟IP 端口
    delay_loop 2
    lb_algo rr
    lb_kind NAT
    persistence_timeout 50
    protocol TCP

    real_server 192.168.174.8 80 {	# 机器真实IP 端口
        weight 3
        notify_down /etc/keepalived/kill.sh
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
            connect_port 80
        }
    }
}

# ct2 配置文件
! Configuration File for keepalived

global_defs {
   router_id LVS_DEVEL
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens33
    virtual_router_id 51
    priority 50
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.174.100
    }

}

virtual_server 192.168.174.100 80 {
    delay_loop 2
    lb_algo rr
    lb_kind NAT
    persistence_timeout 50
    protocol TCP

    real_server 192.168.174.8 80 {
        weight 3
        notify_down /etc/keepalived/kill.sh
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
            connect_port 80
        }
    }
}

/etc/keepalived/kill.sh文件内容：

# 注意赋予执行权限
#! /bin/bash
systemctl stop keepalived

验证，查看虚IP：

[root@ct1 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:96:93:a5 brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.7/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 69302sec preferred_lft 69302sec
    inet 192.168.174.100/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever


[root@ct2 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:cc:c1:4a brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.8/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 69301sec preferred_lft 69301sec
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link tentative noprefixroute dadfailed 
       valid_lft forever preferred_lft forever
    inet6 fe80::8174:b896:90e9:17a3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

关闭ct1 的nginx服务，查看虚IP是否切换：

[root@ct1 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:96:93:a5 brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.7/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 69081sec preferred_lft 69081sec
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
       

[root@ct2 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:cc:c1:4a brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.8/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 69077sec preferred_lft 69077sec
    inet 192.168.174.100/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link tentative noprefixroute dadfailed 
       valid_lft forever preferred_lft forever
    inet6 fe80::8174:b896:90e9:17a3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

重新启动ct1的服务，看是否恢复。

[root@ct1 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:96:93:a5 brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.7/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 68970sec preferred_lft 68970sec
    inet 192.168.174.100/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
       

[root@ct2 keepalived]# ip a
...
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:cc:c1:4a brd ff:ff:ff:ff:ff:ff
    inet 192.168.174.8/24 brd 192.168.174.255 scope global noprefixroute dynamic ens33
       valid_lft 68968sec preferred_lft 68968sec
    inet6 fe80::35f1:e90f:4400:48e3/64 scope link tentative noprefixroute dadfailed 
       valid_lft forever preferred_lft forever
    inet6 fe80::8174:b896:90e9:17a3/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

上面的结果来看，部署成功。

【推广】 免费学中医，健康全家人
原文地址：https://www.cnblogs.com/os-linux/p/15502426.html