反向代理与负载均衡
nginx通常被用作后端服务器的反向代理，这样就可以很方便的实现动静分离以及负载均衡，从而大大提高服务器的处理能力。
nginx实现动静分离，其实就是在反向代理的时候，如果是静态资源，就直接从nginx发布的路径去读取，而不需要从后台服务器获取了。
但是要注意，这种情况下需要保证后端跟前端的程序保持一致，可以使用Rsync做服务端自动同步或者使用NFS、MFS分布式共享存储。
Http Proxy`模块，功能很多，最常用的是`proxy_pass`和`proxy_cache
如果要使用proxy_cache，需要集成第三方的ngx_cache_purge模块，用来清除指定的URL缓存。这个集成需要在安装nginx的时候去做，如：
./configure --add-module=../ngx_cache_purge-1.0 ......
nginx通过upstream模块来实现简单的负载均衡，upstream需要定义在http段内
在upstream段内，定义一个服务器列表，默认的方式是轮询，如果要确定同一个访问者发出的请求总是由同一个后端服务器来处理，可以设置ip_hash，如：
upstream idfsoft.com { // 此字段要写在server字段的前面
ip_hash;
server 127.0.0.1:9080 weight=5;
server 127.0.0.1:8080 weight=5;
server 127.0.0.1:1111;
}
upstream webservers{
server 192.168.91.134 weight=3; // weight表示访问三次134后访问一次147
server 192.168.91.137;
}
注：这个方法本质还是轮询，而且由于客户端的ip可能是不断变化的，比如动态ip，代理，翻墙等，因此ip_hash并不能完全保证同一个客户端总是由同一个服务器来处理。
定义好upstream后，需要在server段内添加如下内容：
server {
location / {
proxy_pass http://webservers; // 这里要和upstream段配置的域名一致
}
}
nginx动静分离实验
实验环境说明：
| 主机名字 | IP | 安装服务 | 系统 |
|---|---|---|---|
| httpd | 192.168.91.134 | Apache | centos8 |
| nginx | 192.168.91.135 | Nginx | centos8 |
| lnmp | 192.168.91.137 | LNMP | centos8 |
安装httpd
编译安装apache查看这篇文章：LAMP
// yum 安装就可以了
#httpd
[root@httpd ~]# yum -y install httpd
// 开启httpd服务
[root@httpd ~]# systemctl enable --now httpd
Created symlink /etc/systemd/system/multi-user.target.wants/httpd.service → /usr/lib/systemd/system/httpd.service.
// 关闭防火墙和selinux
[root@httpd ~]# systemctl disable --now firewalld
Removed /etc/systemd/system/multi-user.target.wants/firewalld.service.
Removed /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
[root@httpd ~]# setenforce 0
[root@httpd ~]# vi /etc/selinux/config
SELINUX=disabled
web 页面访问
安装nginx服务
#nginx
//创建系统用户nginx
[root@nginx ~]# useradd -r -M -s /sbin/nologin nginx
//安装依赖包、包组和使用工具
[root@nginx ~]# yum -y install pcre-devel pcre gcc gcc-c++ openssl-devel zlib zlib-devel make vim wget openssl openssl-devel gd-devel
安装过程略....
[root@nginx ~]# yum -y groups mark install 'Development Tools'
Marked install: Development Tools
//创建日志存放目录
[root@nginx ~]# mkdir -p /var/log/nginx
[root@nginx ~]# chown -R nginx.nginx /var/log/nginx
//下载nginx
[root@nginx ~]# cd /usr/src/
[root@nginx src]# wget https://nginx.org/download/nginx-1.20.1.tar.gz
安装过程略....
//编译安装
[root@nginx src]# ls
debug kernels nginx-1.20.1.tar.gz
[root@nginx src]# tar xf nginx-1.20.1.tar.gz
[root@nginx src]# cd nginx-1.20.1
[root@nginx nginx-1.20.1]# ./configure \
--prefix=/usr/local/nginx \
--user=nginx \
--group=nginx \
--with-debug \
--with-http_ssl_module \
--with-http_realip_module \
--with-http_image_filter_module \
--with-http_gunzip_module \
--with-http_gzip_static_module \
--with-http_stub_status_module \
--http-log-path=/var/log/nginx/access.log \
--error-log-path=/var/log/nginx/error.log
[root@nginx nginx-1.20.1]# make && make install
安装过程略....
[root@nginx nginx-1.20.1]# cd
[root@nginx ~]#
// 配置环境变量
[root@nginx ~]# echo "export PATH=/usr/local/nginx/sbin:$PATH" > /etc/profile.d/nginx.sh
[root@nginx ~]# source /etc/profile.d/nginx.sh
// 编写nginx启动文件
[root@nginx ~]# cat > /usr/lib/systemd/system/nginx.service <<EOF
[Unit]
Description=Nginx server daemon
After=network.target
[Service]
Type=forking
ExecStart=/usr/local/nginx/sbin/nginx
ExecStop=/usr/local/nginx/sbin/nginx -s quit
ExecReload=/bin/kill -HUP \$MAINPID
[Install]
WantedBy=multi-user.target
EOF
// 效果验证
[root@nginx ~]# systemctl daemon-reload
[root@nginx ~]# systemctl enable --now nginx.service
[root@nginx ~]# ss -antl
State Recv-Q Send-Q Local Address:Port Peer Address:Port Process
LISTEN 0 128 0.0.0.0:80 0.0.0.0:*
LISTEN 0 128 0.0.0.0:22 0.0.0.0:*
LISTEN 0 128 [::]:22 [::]:*
// 关闭防火墙和selinux
```shell
[root@nginx ~]# systemctl disable --now firewalld
Removed /etc/systemd/system/multi-user.target.wants/firewalld.service.
Removed /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
[root@nginx ~]# setenforce 0
[root@nginx ~]# vim /etc/selinux/config
SELINUX=disabled
web页面访问
LNMP安装
nginx包下载地址
安装nginx
#lnmp
// 关闭防火墙和selinux
[root@lnmp ~]# systemctl disable --now firewalld
Removed /etc/systemd/system/multi-user.target.wants/firewalld.service.
Removed /etc/systemd/system/dbus-org.fedoraproject.FirewallD1.service.
[root@lnmp ~]# systemctl stop --now firewalld
[root@lnmp ~]# vim /etc/selinux/config
SELINUX=disabled
[root@lnmp ~]# reboot
[root@lnmp ~]# setenforce 0
setenforce: SELinux is disabled
// 创建用户
[root@lnmp ~]# useradd -r -M -s /sbin/nologin nginx
[root@lnmp ~]# id nginx
uid=994(nginx) gid=991(nginx) groups=991(nginx)
// 安装epel源、依赖包、工具包（安装lnmp所有需要的依赖包都在里面）
[root@lnmp ~]# yum -y install epel-release
[root@lnmp ~]# yum -y install pcre-devel openssl openssl-devel gd-devel gcc gcc-c++ make ncurses-devel cmake mariadb-devel ncurses-compat-libs libxml2 libxml2-devel bzip2 bzip2-devel libcurl libcurl-devel libicu-devel libjpeg libjpeg-devel libpng libpng-devel openldap-devel pcre-devel freetype freetype-devel gmp gmp-devel libmcrypt libmcrypt-devel readline readline-devel libxslt libxslt-devel mhash mhash-devel php-mysqlnd libsqlite3x-devel oniguruma libzip-devel
// 将之前下载好的包传上去，并解压
[root@lnmp ~]# cd /usr/src/
[root@lnmp src]# ls
debug
kernels
mysql-5.7.34-linux-glibc2.12-x86_64.tar.gz
nginx-1.20.1.tar.gz
php-8.0.10.tar.gz
[root@lnmp src]# tar xf nginx-1.20.1.tar.gz -C /usr/local/
// 创建日志存放目录
[root@lnmp src]# mkdir -p /var/log/nginx
[root@lnmp src]# chown -R nginx.nginx /var/log/nginx/
// 编译安装
[root@lnmp nginx-1.20.1]# ./configure \
--prefix=/usr/local/nginx \
--user=nginx \
--group=nginx \
--with-debug \
--with-http_ssl_module \
--with-http_realip_module \
--with-http_image_filter_module \
--with-http_gunzip_module \
--with-http_gzip_static_module \
--with-http_stub_status_module \
--http-log-path=/var/log/nginx/access.log \
--error-log-path=/var/log/nginx/error.log \
&& make && make install
// 设置环境变量
[root@lnmp ~]# echo 'export PATH=/usr/local/nginx/sbin:$PATH' > /etc/profile.d/nginx.sh
[root@lnmp ~]# . /etc/profile.d/nginx.sh
[root@lnmp ~]# nginx
[root@lnmp ~]# ss -antl
State Recv-Q Send-Q Local Address:Port Peer Address:Port Process
LISTEN 0 128 0.0.0.0:80 0.0.0.0:*
LISTEN 0 128 0.0.0.0:22 0.0.0.0:*
LISTEN 0 128 [::]:22 [::]:*
安装mysql
mysql包下载链接
#lnmp
// 创建用户
[root@lnmp ~]# useradd -r -M -s /sbin/nologin mysql
// 传包到当前目录然后解压mysql包
[root@lnmp ~]# tar xf /usr/src/mysql-5.7.34-linux-glibc2.12-x86_64.tar.gz -C /usr/local/
// 做软链接
[root@lnmp local]# mv mysql-5.7.34-linux-glibc2.12-x86_64/ mysql
[root@lnmp local]# chown -R mysql.mysql mysql/
// 头文字连接
[root@lnmp local]# ln -s /usr/local/mysql/include/ /usr/include/mysql/
// 库文件
[root@lnmp local]# vim /etc/ld.so.conf.d/mysql.conf
[root@lnmp local]# cat /etc/ld.so.conf.d/mysql.conf
/usr/local/mysql/lib
// 创建数据存放目录
[root@lnmp local]# mkdir /opt/data
[root@lnmp local]# chown -R mysql.mysql /opt/data/
// 设置环境变量
[root@lnmp local]# echo 'export PATH=/usr/local/mysql/bin:$PATH' > /etc/profile.d/mysql.sh
[root@lnmp local]# . /etc/profile.d/mysql.sh
// 初始化
[root@lnmp local]# mysqld --initialize-insecure --user mysql --datadir /opt/data
// 编写配置文件
[root@lnmp local]# cat > /etc/my.cnf << EOF
> [mysqld]
> basedir = /usr/local/mysql/
> datadir = /opt/data/
> socket = /tmp/mysql.sock
> port = 3306
> pid-file = /opt/data/mysql.pid
> user = mysql
> skip-name-resolve
> EOF
// 编写服务控制脚本
[root@lnmp local]# vim /usr/lib/systemd/system/mysqld.service
[Unit]
Description=Mysql server daemon
After=network.target sshd-keygen.target
[Service]
Type=forking
ExecStart=/usr/local/mysql/support-files/mysql.server start
ExecReload=/bin/kill -HUP $MAINPID
ExecStop=/usr/local/mysql/support-files/mysql.server stop
[Install]
WantedBy=multi-user.target
basedir=/usr/local/mysql
datadir=/opt/data
// 启动mysql服务
[root@lnmp local]# systemctl daemon-reload
[root@lnmp local]# systemctl start mysqld
[root@lnmp local]# systemctl enable --now mysqld
Created symlink /etc/systemd/system/multi-user.target.wants/mysqld.service → /usr/lib/systemd/system/mysqld.service.
[root@lnmp local]# ss -antl
State Recv-Q Send-Q Local Address:Port Peer Address:Port Process
LISTEN 0 128 0.0.0.0:80 0.0.0.0:*
LISTEN 0 128 0.0.0.0:22 0.0.0.0:*
LISTEN 0 80 *:3306 *:*
LISTEN 0 128 [::]:22 [::]:*
安装php
php包下载地址
#lnmp
// 把下载好的包传到当前目录然后解压
[root@lnmp ~]# tar xf /usr/src/php-8.0.10.tar.gz -C /usr/local/
[root@lnmp ~]# cd /usr/local/php-8.0.10/
// 编译安装
[root@lnmp php-8.0.10]# ./configure --prefix=/usr/local/php8 \
--with-config-file-path=/etc \
--enable-fpm \
--disable-debug \
--disable-rpath \
--enable-shared \
--enable-soap \
--with-openssl \
--enable-bcmath \
--with-iconv \
--with-bz2 \
--enable-calendar \
--with-curl \
--enable-exif \
--enable-ftp \
--enable-gd \
--with-jpeg \
--with-zlib-dir \
--with-freetype \
--with-gettext \
--enable-mbstring \
--enable-pdo \
--with-mysqli=mysqlnd \
--with-pdo-mysql=mysqlnd \
--with-readline \
--enable-shmop \
--enable-simplexml \
--enable-sockets \
--with-zip \
--enable-mysqlnd-compression-support \
--with-pear \
--enable-pcntl \
--enable-posix \
&& make && make install
// 设置环境变量
[root@lnmp php-8.0.10]# echo 'export PATH=/usr/local/php8/bin:$PATH' > /etc/profile.d/php.sh
[root@lnmp php-8.0.10]# . /etc/profile.d/php.sh
// 配置php
[root@lnmp php-8.0.10]# cp sapi/fpm/init.d.php-fpm /etc/init.d/php-fpm
[root@lnmp php-8.0.10]# chmod +x /etc/init.d/php-fpm
[root@lnmp php-8.0.10]# cd /usr/local/php8
[root@lnmp php8]# cd etc/
[root@lnmp etc]# cp php-fpm.conf.default php-fpm.conf
[root@lnmp etc]# cd php-fpm.d/
[root@lnmp php-fpm.d]# cp www.conf.default www.conf
[root@lnmp php-fpm.d]# ls
www.conf www.conf.default
// 启动服务
[root@lnmp php-fpm.d]# service php-fpm start
Starting php-fpm done
[root@lnmp php-fpm.d]# ss -antl
State Recv-Q Send-Q Local Address:Port Peer Address:Port Process
LISTEN 0 128 127.0.0.1:9000 0.0.0.0:*
LISTEN 0 128 0.0.0.0:80 0.0.0.0:*
LISTEN 0 128 0.0.0.0:22 0.0.0.0:*
LISTEN 0 80 *:3306 *:*
LISTEN 0 128 [::]:22 [::]:*
nginx配置
// 配置网页文件
[root@lnmp ~]# cd /usr/local/nginx/html/
[root@lnmp html]# vim index.php
[root@lnmp html]# cat index.php
<?php
phpinfo();
?>
[root@lnmp html]# chown -R nginx.nginx index.php
//修改配置文件
[root@lnmp nginx]# vim conf/nginx.conf
server {
listen 80;
server_name localhost;
#charset koi8-r;
#access_log logs/host.access.log main;
location / {
root html;
index index.php index.html index.htm;
}
location ~ \.php$ {
root html;
fastcgi_pass 127.0.0.1:9000;
fastcgi_index index.php;
fastcgi_param SCRIPT_FILENAME /usr/local/nginx/html$fastcgi_script_name;
include fastcgi_params;
}
// 重新加载nginx
[root@lnmp nginx]# nginx -s reload
web 页面访问
以上页面都访问成功之后就可以开始配置负载均衡和动静分离了
在nginx主机上配置负载均衡
#nginx
[root@nginx ~]# vim /usr/local/nginx/conf/nginx.conf
upstream test { // 此字段要在server字段前面，之前提到过的
server 192.168.91.134;
server 192.168.91.137;
}
server {
listen 80;
server_name localhost;
#charset koi8-r;
#access_log logs/host.access.log main;
location / {
proxy_pass http://test; // test要与上面的upstream后面所跟的一样
}
// 检查语法
[root@nginx ~]# nginx -t
nginx: the configuration file /usr/local/nginx/conf/nginx.conf syntax is ok
nginx: configuration file /usr/local/nginx/conf/nginx.conf test is successful
// 重新加载
[root@nginx ~]# nginx -s reload
web页面访问192.168.91.135
在nginx主机上配置动静分离
#nginx
[root@nginx ~]# vim /usr/local/nginx/conf/nginx.conf
upstream test1 {
server 192.168.91.134;
}
upstream test2 {
server 192.168.91.137;
}
server {
listen 80;
server_name localhost;
#charset koi8-r;
#access_log logs/host.access.log main;
location / {
proxy_pass http://test1;
}
location ~ \.php$ {
proxy_pass http://test2;
}
#error_page 404 /404.html;
// 检查语法
[root@nginx ~]# nginx -t
nginx: the configuration file /usr/local/nginx/conf/nginx.conf syntax is ok
nginx: configuration file /usr/local/nginx/conf/nginx.conf test is successful
// 重新加载
[root@nginx ~]# nginx -s reload
访问根目录下的静态资源会自动跳转到192.168.91.134上进行访问
访问根目录下的.php动态资源会自动跳转到192.168.91.137上进行访问
