安装Nginx

soulballad约 2542 字大约 8 分钟

安装Nginx

下载安装

这⾥使⽤的是 1.17.10. 版： nginx-1.17.10.tar.gz ，放到对应⽬录下

# 解压安装包
tar -zxvf nginx-1.17.0.tar.gz -C /usr/local
# 安装依赖
yum -y install pcre-devel openssl openssl-devel
# 进入目录
cd /usr/local/nginx-1.17.0
# 编译安装
./configure
make && make install

启动停止

# 启动服务
/usr/local/nginx/sbin/nginx
# 停止服务
/usr/local/nginx/sbin/nginx -s stop
# 重新加载配置
/usr/local/nginx/sbin/nginx -s reload

注意其配置⽂件位于：

/usr/local/nginx/conf/nginx.conf

Nginx主备模式

使用一个vip地址，前端使用2台机器，一台做主，一台做备，但同时只有一台机器工作，另一台备份机器在主机器不出现故障的时候，永远处于浪费状态，对于服务器不多的网站，该方案不经济实惠。

序号	域名	作用	服务器IP	角色	Nginx版本	keepalived
1	cdh1	nginx1	172.18.11.111	Master	openresty/1.21.4.1	keepalived-2.1.5
2	cdh2	nginx2	172.18.11.112	Backup	openresty/1.21.4.1	keepalived-2.1.5
3		VIP	172.18.11.110

Master-Keepalived

global_defs {   
   router_id cdh1
}
vrrp_script check_nginx_alive {
    script "/usr/local/script/check_nginx_alive.sh"
    interval 2
    weight -5
    fall 3
    rise 2
}
vrrp_instance VI_1 {
    state MASTER
    interface enp0s8
    virtual_router_id 51
    priority 150
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        172.18.11.110
    }
    track_script {
        check_nginx_alive
    }
}

Backup-Keepalived

在备用nginx服务器172.16.2.51上，配置一样，就三点不同，一点必须相同：

router_id 不同；
state BACKUP 不同；
priority 不同；
virtual_router_id 必相同。配置如下：

global_defs {   
   router_id cdh2
}
vrrp_script check_nginx_alive {
    script "/usr/local/script/check_nginx_alive.sh"
    interval 2
    weight -5
    fall 3
    rise 2
}
vrrp_instance VI_1 {
    state BACKUP
    interface enp0s8
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        172.18.11.110
    }
    track_script {
        check_nginx_alive
    }
}

check_nginx_alive

于待会测试，所以第一个简单脚本就可以了，只要判断nginx进程没有数值，则停止keepalived服务。测试脚本如下：

#! /bin/bash
pidof nginx
if [ $? -ne 0 ];then
    killall keepalived
fi

如果测试完，可以加个尝试启动nginx，如果尝试失败两次就停止keepalived服务。脚本如下：

#!/bin/bash
counter=$(ps -C nginx --no-heading|wc -l)
if [ "${counter}" = "0" ]; then
    /usr/local/openresty/nginx/sbin/nginx
    sleep 2
    counter=$(ps -C nginx --no-heading|wc -l)
    if [ "${counter}" = "0" ]; then
        killall keepalived 
    fi
fi

添加运行权限

chmod +x /usr/local/script/check_nginx_alive.sh

Nginx配置

nginx服务器中的nginx配置：只需要把 server_name 改成VIP的IP即可，其他无需更改，负载均衡时也只要访问这个VIP地址即可。

修改 /usr/local/openresty/nginx/html/index.html 中内容，添加一行记录区分当前服务器 <p>当前Nginx服务器IP: 172.18.11.112</p>

server {
    listen       80;
    server_name  172.18.11.110;
    location / {
        root   html;
        index  index.html index.htm;
    }   
}

测试验证

依次在两台nginx服务器启动，并重启 keepalived

systemctl restart nginx.service
syetemctl restart keepalived

分别在nginx主备两台用ip addr查看IP地址：主nginx1的网卡此时已经自动获取VIP，备nginx2则没有处于空闲状态
在浏览器访问VIP：172.18.11.110，也正常显示： 当前Nginx服务器IP: 172.18.11.111
通过命令 nginx -s stop 关闭nginx1，发现显示内容变成： 当前Nginx服务器IP: 172.18.11.112
最后在主nginx1上启动nginx和keepalived后，nginx1重新抢回VIP，一切恢复正常。备nginx2恢复空闲状态。可自行测试查看结果。

Nginx双主模式

使用两个vip地址，前端使用2台机器，互为主备，同时有两台机器工作，当其中一台机器出现故障，两台机器的请求转移到一台机器负担，非常适合于当前架构环境

序号	域名	作用	服务器IP	角色	Nginx版本	keepalived
1	cdh1	nginx1	172.18.11.111	Master/Backup	openresty/1.21.4.1	keepalived-2.1.5
2	cdh2	nginx2	172.18.11.112	Master/Backup	openresty/1.21.4.1	keepalived-2.1.5
3		VIP1	172.18.11.110
4		VIP2	172.18.11.120

当了解主备模式后，双主模式就容易配置多了。只需要在每台keepalived配置文件，加上一个vrrp_instance命名vrrp_instance VI_2即可，更改几个参数，设置另一个 VIP：172.18.11.120

nginx1：state BACKUP ，priority 100， virtual_router_id 52
nginx2：state MASTER ，priority 150， virtual_router_id 52

Nginx1-Keepalived

global_defs {   
   router_id cdh1
}
vrrp_script check_nginx_alive {
    script "/usr/local/script/check_nginx_alive.sh"
    interval 2
    weight -5
    fall 3
    rise 2
}
vrrp_instance VI_1 {
    state MASTER
    interface enp0s8
    virtual_router_id 51
    priority 150
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        172.18.11.110
    }
    track_script {
        check_nginx_alive
    }
}   
vrrp_instance VI_2 {
    state BACKUP
    interface enp0s8
    virtual_router_id 52
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        172.18.11.120
    }
    track_script {
        check_nginx_alive
    }  
}

Nginx2-Keepalived

global_defs {   
   router_id cdh2
}
vrrp_script check_nginx_alive {
    script "/usr/local/script/check_nginx_alive.sh"
    interval 2
    weight -5
    fall 3
    rise 2
}
vrrp_instance VI_1 {
    state BACKUP
    interface enp0s8
    virtual_router_id 51
    priority 150
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        172.18.11.110
    }
    track_script {
        check_nginx_alive
    }
 }
  
vrrp_instance VI_2 {
    state MASTER
    interface enp0s8
    virtual_router_id 52
    priority 150
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        172.18.11.120
    }
    track_script {
        check_nginx_alive
    }  
}

Nginx配置

同样，在nginx做负载均衡时，需要在nginx的配置文件中，server_name加上这个 172.18.11.120 这个VIP2的地址，配置如下：

server {
    listen       80;
    server_name  172.18.11.110;
    server_name  172.18.11.120;
    location / {
        root   html;
        index  index.html index.htm;
    }   
}

测试验证

依次启动两台机器上的服务

systemctl restart nginx.service
syetemctl restart keepalived

在浏览器分别访问 172.18.11.110 和 172.18.11.120 都可以负载均衡至nginx1和nginx2。

双主模式配置完成！！

Lvs+Keepalived高可用

keepalived实现虚拟IP（VIP），client访问VIP，连接到keepalived-master,keepliaved-master服务器通过LVS轮询机制将请求负载到nginx-1和nginx-2。

主机	域名	IP	作用	版本
1	cdh1	172.18.11.111	Nginx1	openresty/1.21.4.1
2	cdh2	172.18.11.112	Nginx2	openresty/1.21.4.1
3	cdh1	172.18.11.111	Master	keepalived-2.1.5
4	cdh2	172.18.11.112	Backup	keepalived-2.1.5
5		172.18.11.110	虚拟IP(VIP)

lo网卡配置脚本

此环境配置LVS DR 模式，需要在后端nginx服务器lo网卡配置LVS的VIP

vim /etc/init.d/realserver

#虚拟的vip 改为自己环境的vip
SNS_VIP=172.18.11.110
/etc/rc.d/init.d/functions
case "$1" in        #case语句 $1传递给该shell脚本的第一个参数
    start)
        ifconfig lo:0 $SNS_VIP netmask 255.255.255.255 broadcast $SNS_VIP #设置 lo:0 VIP netmask 及广播
        /sbin/route add -host $SNS_VIP dev lo:0     #route del 增加本地路由
        echo "1" >/proc/sys/net/ipv4/conf/lo/arp_ignore
        echo "2" >/proc/sys/net/ipv4/conf/lo/arp_announce
        echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore
        echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce
        sysctl -p >/dev/null 2>&1
        echo "RealServer Start OK"
        ;;
    stop)
        ifconfig lo:0 down
        route del $SNS_VIP >/dev/null 2>&1          #route del 删除本地路由
        echo "0" >/proc/sys/net/ipv4/conf/lo/arp_ignore
        echo "0" >/proc/sys/net/ipv4/conf/lo/arp_announce
        echo "0" >/proc/sys/net/ipv4/conf/all/arp_ignore
        echo "0" >/proc/sys/net/ipv4/conf/all/arp_announce
        echo "RealServer Stoped"
        ;;
    *)
    echo "Usage: $0 {start|stop}"       #$0 是脚本本身的名字
    exit 1                              #表示进程正常退出
esac                                    #case结束
exit 0                                  #表示进程非正常退出

在 nginx1 和 nginx2 分别执行该脚本

chmod 755 /etc/init.d/realserver
chmod 755 /etc/rc.d/init.d/functions
service realserver start

Master-Keepalived

在 Master 配置

! Configuration File for keepalived

global_defs {
   router_id NG1 # 设置lvs的id，在一个网络内应该是唯一的
}

vrrp_instance VI_1 {
    state MASTER #指定Keepalived的角色，MASTER为主，BACKUP为备 一定大写
    interface enp0s8 #服务器网卡名
    virtual_router_id 51  #虚拟路由编号，主备要一致
    priority 100 #定义优先级，数字越大，优先级越高，主必须大于备
    advert_int 1 #检查间隔，默认为1s
    authentication { #这里配置的密码最多为8位，主备要一致，否则无法正常通讯
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        172.18.11.110 #定义虚拟IP(VIP)为192.168.100.202，可多设，每行一个
    }
}

virtual_server 172.18.11.110 80 {
    delay_loop 6 # 设置健康检查时间，单位是秒
    lb_algo rr #rr代表正常轮询模式，正式环境建议使用wlc加权最小连接数轮询
    lb_kind DR #DR模式：返回请求时，不走LVS，直接返回到客户端。
    nat_mask 255.255.255.0
    persistence_timeout 0
    protocol TCP

    real_server 172.18.11.111 80 { #后端服务器地址
        weight 1  # 配置节点权值，数字越大权重越高
        TCP_CHECK {
            retry 3
            connect_port 80
            connect_timeout 10
            delay_before_retry 3
        }
    }
    real_server 172.18.11.112 80 {
        weight 1
        TCP_CHECK {
            retry 3
            connect_port 80
            connect_timeout 10
            delay_before_retry 3
        }
    }
}

Backup-Keepalived

在 Backup 配置

! Configuration File for keepalived

global_defs {
   router_id NG2
}

vrrp_instance VI_1 {
    state BACKUP  #此处改为BACKUP,一定要大写**
    interface enp0s8
    virtual_router_id 51
    priority 90  #此处改为90，要比master小**
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        172.18.11.110
    }
}

virtual_server 172.18.11.110 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    nat_mask 255.255.255.0
    persistence_timeout 50
    protocol TCP

    real_server 172.18.11.111 80 {
        weight 1
        TCP_CHECK {
            retry 3
            connect_port 80
            connect_timeout 10
            delay_before_retry 3
        }
    }
    real_server 172.18.11.112 80 {
        weight 1
        TCP_CHECK {
            retry 3
            connect_port 80
            connect_timeout 10
            delay_before_retry 3
        }
    }
}

测试验证

# 查看当前配置的虚拟服务和各个RS的权重
ipvsadm -Ln
# 查看当前ipvs模块中记录的连接
ipvsadm -Lnc

通过访问 172.18.11.110，可以正常显示

停用主Keepalived

systemctl stop keepalived.service

停用前，主keepalived的VIP还在 ip a show dev enp0s8

[root@cdh1 script]# ip a show dev enp0s8
3: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
	link/ether 08:00:27:29:90:d5 brd ff:ff:ff:ff:ff:ff
	inet 172.18.11.111/24 brd 172.18.11.255 scope global enp0s8
		valid_lft forever preferred_lft forever
	inet 172.18.11.110/32 scope global enp0s8
		valid_lft forever preferred_lft forever
	inet6 fe80::a00:27ff:fe29:90d5/64 scope link
		valid_lft forever preferred_lft forever
[root@cdh1 script]# systemctl stop keepalived
[root@cdh1 script]# ip a show dev enp0s8
3: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
	link/ether 08:00:27:29:90:d5 brd ff:ff:ff:ff:ff:ff
	inet 172.18.11.111/24 brd 172.18.11.255 scope global enp0s8
		valid_lft forever preferred_lft forever
	inet6 fe80::a00:27ff:fe29:90d5/64 scope link
		valid_lft forever preferred_lft forever
[root@cdh1 script]#

停用后，VIP出现在从backup上 ip a show dev enp0s8

[root@cdh2 script]# ip a show dev enp0s8
3: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
	link/ether 08:00:27:51:d4:37 brd ff:ff:ff:ff:ff:ff
	inet 172.18.11.112/24 brd 172.18.11.255 scope global enp0s8
		valid_lft forever preferred_lft forever
	inet6 fe80::a00:27ff:fe51:d437/64 scope link
		valid_lft forever preferred_lft forever
[root@cdh2 script]# ip a show dev enp0s8
3: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
	link/ether 08:00:27:51:d4:37 brd ff:ff:ff:ff:ff:ff
	inet 172.18.11.112/24 brd 172.18.11.255 scope global enp0s8
		valid_lft forever preferred_lft forever
	inet 172.18.11.110/32 scope global enp0s8
		valid_lft forever preferred_lft forever
	inet6 fe80::a00:27ff:fe51:d437/64 scope link
		valid_lft forever preferred_lft forever
[root@cdh2 script]#

此时通过172.18.11.110可以正常访问，当把主Keepalived重启启动后，VIP重新回到主Keepalived

[root@cdh1 script]# ps -ef|grep keepalived
root     23345  4493  0 21:34 pts/0    00:00:00 grep --color=auto keepalived
[root@cdh1 script]# systemctl start keepalived
[root@cdh1 script]# ip a show dev enp0s8
3: enp0s8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
	link/ether 08:00:27:29:90:d5 brd ff:ff:ff:ff:ff:ff
	inet 172.18.11.111/24 brd 172.18.11.255 scope global enp0s8
		valid_lft forever preferred_lft forever
	inet 172.18.11.110/32 scope global enp0s8
		valid_lft forever preferred_lft forever
	inet6 fe80::a00:27ff:fe29:90d5/64 scope link
		valid_lft forever preferred_lft forever
[root@cdh1 script]#

测试停用nginx1
停用前，两台nginx存在 ipvsadm -l

[root@cdh1 script]# ipvsadm -l
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.18.11.110:http rr
  -> cdh1:http                    Route   1      0          0
  -> cdh2:http                    Route   1      2          0

停用nginx1，发现只有一个172.18.11.112的ip，挂掉的服务已经被移除，此时再去访问只能访问172.18.11.112的nginx

[root@cdh1 script]# ipvsadm -l
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.18.11.110:http rr
  -> cdh1:http                    Route   1      0          0
  -> cdh2:http                    Route   1      2          0
[root@cdh1 script]# nginx -s stop
[root@cdh1 script]# ipvsadm -l
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.18.11.110:http rr
  -> cdh2:http                    Route   1      2          0
[root@cdh1 script]#

参考：

安装Nginx

# 安装Nginx

# 安装Nginx

# 下载安装

# 启动停止

# Nginx主备模式

# Master-Keepalived

# Backup-Keepalived

# check_nginx_alive

# Nginx配置

# 测试验证

# Nginx双主模式

# Nginx1-Keepalived

# Nginx2-Keepalived

# Nginx配置

# 测试验证

# Lvs+Keepalived高可用

# lo网卡配置脚本

# Master-Keepalived

# Backup-Keepalived

# 测试验证

安装Nginx

安装Nginx

下载安装

启动停止

Nginx主备模式

Master-Keepalived

Backup-Keepalived

check_nginx_alive

Nginx配置

测试验证

Nginx双主模式

Nginx1-Keepalived

Nginx2-Keepalived

Nginx配置

测试验证

Lvs+Keepalived高可用

lo网卡配置脚本

Master-Keepalived

Backup-Keepalived

测试验证