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 # 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; } }