nginx代理与负载均衡

nginx代理与负载均衡

  • 代理
  • 负载均衡

 

一、代理

  将流量平均分配

  1.代理的方式

    1)正向代理

    找完代理之后,还需要找服务器

    应用:VPN

    2)反向代理

    只需要找代理,不需要找服务器

    应用:负载均衡

  2.nginx代理服务支持的协议

ngx_http_uwsgi_module        : Python
ngx_http_fastcgi_module        : PHP 
ngx_http_scgi_module        : Java
ngx_http_v2_module            : Golang
ngx_http_proxy_module        : HTTP

  3.nginx代理实践

lb01 ---> web01

    1)部署web01

[root@web01 conf.d]# cat game5.conf 
server {
    listen 80;
    server_name 192.168.15.7;
    location / {
        root /opt/Super_Marie;
    index index.html;
    }
    location ~ /images {
        root /opt/image;
    }
}

    2)部署lb01

部署nginx

# 下载Nginx源代码包 [root@lb01
~]# wget https://nginx.org/download/nginx-1.20.2.tar.gz # 解压 [root@lb01 ~]# tar -xf nginx-1.20.2.tar.gz # 进入源代码目录 [root@lb01 ~]# cd nginx-1.20.2 # 安装依赖包 [root@lb01 nginx-1.20.2]# yum install openssl openssl-devel zlib zlib-devel -y # 设置编译参数 [root@lb01 nginx-1.20.2]# ./configure --with-http_gzip_static_module --with-stream --with-http_ssl_module # 编译 [root@lb01 nginx-1.20.2]# make # 安装 [root@lb01 nginx-1.20.2]# make install # 优化 [root@lb01 nginx]# mkdir /etc/nginx [root@lb01 nginx]# mv /usr/local/nginx/conf/* /etc/nginx/ [root@lb01 nginx]# mkdir /etc/nginx/conf.d [root@lb01 nginx]# groupadd www -g 666 [root@lb01 nginx]# useradd www -u 666 -g 666 -M -r -s /sbin/nologin [root@lb01 nginx]# vim /usr/lib/systemd/system/nginx.service [Unit] Description=nginx - high performance web server Documentation=http://nginx.org/en/docs/ After=network-online.target remote-fs.target nss-lookup.target Wants=network-online.target [Service] Type=forking PIDFile=/var/run/nginx.pid ExecStart=/usr/sbin/nginx -c /etc/nginx/nginx.conf ExecReload=/bin/sh -c "/bin/kill -s HUP $(/bin/cat /var/run/nginx.pid)" ExecStop=/bin/sh -c "/bin/kill -s TERM $(/bin/cat /var/run/nginx.pid)" [Install] WantedBy=multi-user.target [root@lb01 sbin]# ln -s /etc/nginx/nginx.conf /usr/local/nginx/conf/nginx.conf [root@lb01 sbin]# mv /usr/local/nginx/sbin/nginx /usr/sbin/ [root@lb01 sbin]# mkdir /var/log/nginx [root@lb01 sbin]# systemctl start nginx
部署反向代理

[root@lb01 conf.d]# cat /etc/nginx/conf.d/game.conf 
server {
    listen 80;
    server_name _;
    location / {
        proxy_pass http://172.16.1.7:80;
    }
}

  4.nginx代理常用参数

    1)添加发往后端服务器的请求头信息

Syntax:    proxy_set_header field value;
Default:    proxy_set_header Host $http_host;
            proxy_set_header Connection close;
Context:    http, server, location
 
# 用户请求的时候HOST的值是linux.proxy.com, 那么代理服务会像后端传递请求的还是linux.proxy.com
proxy_set_header Host $http_host;
# 将$remote_addr的值放进变量X-Real-IP中,$remote_addr的值为客户端的ip
proxy_set_header X-Real-IP $remote_addr;
# 客户端通过代理服务访问后端服务, 后端服务通过该变量会记录真实客户端地址
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

    2)代理到后端的TCP连接、响应、返回等超时时间

#nginx代理与后端服务器连接超时时间(代理连接超时)
Syntax: proxy_connect_timeout time;
Default: proxy_connect_timeout 60s;
Context: http, server, location
 
#nginx代理等待后端服务器的响应时间
Syntax:    proxy_read_timeout time;
Default:    proxy_read_timeout 60s;
Context:    http, server, location
 
#后端服务器数据回传给nginx代理超时时间
Syntax: proxy_send_timeout time;
Default: proxy_send_timeout 60s;
Context: http, server, location

proxy_connect_timeout 1s;
proxy_read_timeout 3s;
proxy_send_timeout 3s;

    3)proxy_buffer代理缓冲区

#nignx会把后端返回的内容先放到缓冲区当中,然后再返回给客户端,边收边传, 不是全部接收完再传给客户端
Syntax: proxy_buffering on | off;
Default: proxy_buffering on;
Context: http, server, location
 
#设置nginx代理保存用户头信息的缓冲区大小
Syntax: proxy_buffer_size size;
Default: proxy_buffer_size 4k|8k;
Context: http, server, location
 
#proxy_buffers 缓冲区
Syntax: proxy_buffers number size;
Default: proxy_buffers 8 4k|8k;
Context: http, server, location

    4)配置代理优化文件

[root@lb01 ~]# vim /etc/nginx/proxy_params 
proxy_set_header Host $http_host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_connect_timeout 10s;
proxy_read_timeout 10s;
proxy_send_timeout 10s;
proxy_buffering on;
proxy_buffer_size 8k;
proxy_buffers 8 8k;

[root@lb01 conf.d]# cat game.conf 
server {
    listen 80;
    server_name _;
    location / {
        proxy_pass http://172.16.1.7:80;
        include /etc/nginx/proxy_params;
    }
}

 

二、负载均衡

  1.负载均衡的架构

    通过代理将流量按照一定的比例,转发到后端

  2.负载均衡的实现

    1)实现

将后端服务打包成一个IP连接池。

1.反向代理
server {
       listen 80;
       server_name _;
       location / {
        proxy_pass http://[连接池];
       }
}

2.IP连接池
upstream [连接池名称] {
    server [ip]:[port];
    server [ip]:[port];
    server [ip]:[port];
}

[root@lb01 conf.d]# cat game.conf 
upstream supermarie {
    server 172.16.1.7:80;
    server 172.16.1.8:80;
    server 172.16.1.9:80;
}

server {
    listen 80;
    server_name _;
    location / {
        proxy_pass http://supermarie;
        include /etc/nginx/proxy_params;
    }
}

    2)负载均衡的比例

      轮询

# 默认情况下,Nginx负载均衡的轮询状态。
upstream supermarie {
    server 172.16.1.7:80;
    server 172.16.1.8:80;
    server 172.16.1.9:80;
}

      权重

# Nginx中的权重0-100,数字越大,权重越高。
upstream supermarie {
    server 172.16.1.7:80 weight=9;
    server 172.16.1.8:80 weight=5;
    server 172.16.1.9:80 weight=1;
}

      ip_hash

# 每一个IP固定访问某一个后端。
upstream supermarie {
    server 172.16.1.7:80;
    server 172.16.1.8:80;
    server 172.16.1.9:80;
    ip_hash;
}

  3.负载均衡后端状态

状态 概述
down 当前的server暂时不参与负载均衡
backup 预留的备份服务器
max_fails 允许请求失败的次数
fail_timeout 经过max_fails失败后, 服务暂停时间

    1)down

# 暂时不分配流量
upstream supermarie {
    server 172.16.1.7:80 down;
    server 172.16.1.8:80;
    server 172.16.1.9:80;
}

server {
    listen 80;
    server_name _;
    location / {
        proxy_pass http://supermarie;
        include /etc/nginx/proxy_params;
    }
}

    2)backup

# 只有当所有的机器全部宕机,才能启动。
upstream supermarie {
    server 172.16.1.7:80 backup;
    server 172.16.1.8:80;
    server 172.16.1.9:80;
}

server {
    listen 80;
    server_name _;
    location / {
        proxy_pass http://supermarie;
        include /etc/nginx/proxy_params;
    }
}

    3)max_fails、fail_timeout

# max_fails

# proxy_next_upstream 后端错误标识

[root@lb01 ~]# cat /etc/nginx/conf.d/game.conf 
upstream supermarie {
    server 172.16.1.7:80 max_fails=3 fail_timeout=3s;
    server 172.16.1.8:80 max_fails=3 fail_timeout=3s;
    server 172.16.1.9:80 max_fails=3 fail_timeout=3s;
}

server {
    listen 80;
    server_name _;
    location / {
        proxy_pass http://supermarie;
        proxy_next_upstream error timeout invalid_header http_500 http_502 http_503 http_404; 
        include /etc/nginx/proxy_params;
    }
}
注意:proxy_next_upstream error timeout invalid_header http_500 http_503 http_404; 

error             # 与服务器建立连接,向其传递请求或读取响应头时发生错误;
timeout           # 在与服务器建立连接,向其传递请求或读取响应头时发生超时;
invalid_header    # 服务器返回空的或无效的响应;
http_500          # 服务器返回代码为500的响应;
http_502          # 服务器返回代码为502的响应;
http_503          # 服务器返回代码为503的响应;
http_504          # 服务器返回代码504的响应;
http_403          # 服务器返回代码为403的响应;
http_404          # 服务器返回代码为404的响应;
http_429          # 服务器返回代码为429的响应(1.11.13);
non_idempotent    # 通常,请求与 非幂等 方法(POST,LOCK,PATCH)不传递到请求是否已被发送到上游服务器(1.9.13)的下一个服务器; 启用此选项显式允许重试此类请求;
off               # 禁用将请求传递给下一个服务器。

  4.负载均衡部署BBS

    1)部署后端服务

      部署Python

1.创建用户
[root@web01 opt]# groupadd django -g 888
[root@web01 opt]# useradd django -u 888 -g 888 -r -M -s /bin/sh

2.安装依赖软件
[root@web01 opt]# yum install python3 libxml* python-devel gcc* pcre-devel openssl-devel python3-devel -y

      部署Django和uwsgi

3.安装Django和uwsgi
[root@web01 opt]# pip3 install django==1.11
[root@web01 opt]# pip3 install uwsgi
[root@web01 opt]# pip3 install pymysql

4.创建项目
[root@web01 opt]# unzip bbs.zip 
[root@web03 bbs]# pwd
/opt/bbs
[root@web03 bbs]# vim bbs/settings.py 
ALLOWED_HOSTS = ['*']
DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': 'bbs',
        'USER': 'root',
        'PASSWORD': '123456',
        'HOST': '172.16.1.61',
        'PORT': 3306,
        'CHARSET': 'utf8'
    }
}

# 启动测试
[root@web01 bbs]# python3 manage.py runserver 0.0.0.0:8000

    配置并启动

5.编辑项目配置文件
[root@localhost ~]# cat /opt/linux/myweb_uwsgi.ini 
[uwsgi]
# 端口号
socket            = :8000
# 指定项目的目录
chdir           = /opt/bbs
# wsgi文件路径
wsgi-file       = bbs/wsgi.py
# 模块wsgi路径
module          = bbs.wsgi
# 是否开启master进程
master          = true
# 工作进程的最大数目
processes       = 4
# 结束后是否清理文件
vacuum          = true

6.启动uwsgi
[root@web01 linux]# uwsgi -d --ini myweb_uwsgi.ini --uid 666

-d       : 以守护进程方式运行
--ini : 指定配置文件路径
--uid : 指定uid

TCP 服务

7.编辑Nginx配置文件
[root@localhost ~]# cat /etc/nginx/conf.d/python.conf 
server {
    listen 80;
    server_name py.test.com;
    location / { 
        include uwsgi_params;
        uwsgi_pass 127.0.0.1:8000;
        uwsgi_read_timeout 2;
        uwsgi_param UWSGI_SCRIPT bbs.wsgi;
        uwsgi_param UWSGI_CHDIR /opt/bbs;
        index  index.html index.htm;
        client_max_body_size 35m;
    }
}

8.重启Nginx配置
systemctl restart nginx

    2)部署负载均衡

[root@lb01 conf.d]# cat python.conf 
upstream bbs {
    server 172.16.1.7:80 max_fails=3 fail_timeout=3s;
    server 172.16.1.8:80 max_fails=3 fail_timeout=3s;
    server 172.16.1.9:80 max_fails=3 fail_timeout=3s;
}

server {
    listen 80;
    server_name py.test.com;
    location / {
        proxy_pass http://bbs;
        proxy_next_upstream error timeout invalid_header http_500 http_502 http_503 http_404; 
        include /etc/nginx/proxy_params;
    }
}

 

posted @ 2022-01-06 22:01  尤露  阅读(83)  评论(1)    收藏  举报