nginx实现动静分离

一、简单配置nginx的动静分离

假设web1为静态服务器，web2为动态服务器，node2做代理

1.1 根据目录分开

web1只处理静态请求

[root@web1 ~]# mkdir -p /var/www/www/image
[root@web1 ~]# yum -y install lrzsz
[root@web1 ~]# cd /var/www/www/image/
[root@web1 image]# rz
[root@web1 image]# ll
-rw-r--r--. 1 root root 156848 Mar 13 11:31 nhrzyx.png
[root@web2 ~]# vim /etc/httpd/conf/httpd.conf 
 DocumentRoot "/var/www/www"
[root@web2 ~]# systemctl restart httpd

web2只处理动态请求

[root@web2 ~]# mkdir -p /var/www/www/dynamic
[root@web2 ~]# echo dynamic10 > /var/www/www/dynamic/index.html
[root@web2 ~]# vim /etc/httpd/conf/httpd.conf 
 DocumentRoot "/var/www/www"
[root@web2 ~]# systemctl restart httpd

访问测试

http://172.25.254.134/image/nhrzyx.png

http://172.25.254.135/dynamic/index.html

1.2 通过请求分离

配置代理

[root@lb01 conf]# vim nginx.conf
worker_processes  1;
events {
    worker_connections  1024;
}
http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;
upstream  stack_pools {
        server 172.25.254.134:80 weight=5;
}
upstream  dynamic_pools {
        server 172.25.254.135:80 weight=5;
}
    server {
        listen       80;
        server_name  www.lbtest.com;
        location / {
            root   html;
            index  index.html index.htm;
            proxy_set_header Host $host;
            proxy_pass http://dynamic_pools;
        }
        location /image/ {
            proxy_set_header Host $host;
        proxy_pass http://stack_pools;
        }
        location /dynamic/ {
            proxy_set_header Host $host;
        proxy_pass http://dynamic_pools;
        }
    }
}
[root@lb01 conf]# nginx -s reload

配置hosts ，浏览器访问测试

172.25.254.131  www.lbtest.com

http://www.lbtest.com/image/nhrzyx.png

http://www.lbtest.com/dynamic/

1.3 根据扩展名分离

[root@lb01 conf]# vim nginx.conf

worker_processes  1;
events {
    worker_connections  1024;
}
http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;
upstream  stack_pools {
        server 172.25.254.134:80 weight=5;
}
upstream  dynamic_pools {
        server 172.25.254.135:80 weight=5;
}
    server {
        listen       80;
        server_name  www.lbtest.com;
        location / {
            root   html;
            index  index.html index.htm;
            proxy_set_header Host $host;
            proxy_pass http://dynamic_pools;
        }
        location ~ .*.(jpg|png|gif|css|js|swf|bmp|jsp|php|asp)$ {
        proxy_set_header Host $host;
        proxy_pass http://stack_pools;
        }
    }
}
[root@lb01 conf]# nginx -s reload

http://www.lbtest.com/image/nhrzyx.png 

1.4 根据客户端标识进行分离

http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;
upstream  stack_pools {
        server 172.25.254.134:80 weight=5;
}
upstream  dynamic_pools {
        server 172.25.254.135:80 weight=5;
}
    server {
        listen       80;
        server_name  www.lbtest.com;
        location / {
                if ($http_user_agent ~* "MSIE")
                {
                        proxy_pass http://dynamic_pools;
                }
                if ($http_user_agent ~* "firefox")
                {
                        proxy_pass http://stack_pools;
                }
        }
        proxy_set_header Host $host;
        }
}
[root@web1 image]# echo stack_web>> /var/www/www/test.html
[root@web1 image]# systemctl restart httpd

[root@web2 ~]# echo dynamic_web>>/var/www/www/test.html
[root@web2 ~]# systemctl restart httpd

分别使用IE和火狐浏览器访问

http://www.lbtest.com/test.html

1.5 使用客户端的pc和移动分离

http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;
upstream  stack_pools {
        server 172.25.254.134:80 weight=5;
}
upstream  dynamic_pools {
        server 172.25.254.135:80 weight=5;
}
    server {
        listen       80;
        server_name  www.lbtest.com;
        location / {
                if ($http_user_agent ~* "iphone")
                {
                        proxy_pass http://dynamic_pools;
                }
                if ($http_user_agent ~* "android")
                {
                        proxy_pass http://stack_pools;
                }
        }
        proxy_set_header Host $host;
        }
}

分别使用安卓和iphone访问测试

http://www.lbtest.com/test.html

二 、优化

[root@node2 ~]# vim /etc/sysctl.conf

net.ipv4.tcp_fin_timeout = 2
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_keepalive_time =600
net.ipv4.ip_local_port_range = 4000  65000
net.ipv4.tcp_max_syn_backlog = 16348
net.ipv4.tcp_max_tw_buckets = 36000
net.ipv4.tcp_syn_retries = 1
net.ipv4.tcp_synack_retries = 1
net.ipv4.tcp_max_orphans = 16384
net.core.somaxconn = 16384
net.core.netdev_max_backlog = 18364

proxy_next_upstream error timeout  invalid_header http_500 http_502_http_503  http_504;
nginx尝试连接后端主机失败的次数你，这个数是配合proxy_next_upstream，fastcgi_next_upstream，和memcached_next_upstream这三个参数来使用的，当nginx接受后端服务器返回这三个数定义的状态码的时候，会将这个请求转发给正常的后端服务器，例如404,502,503.Max_fails默认值是1

[root@node2 ~]# sysctl -p

简单介绍keepalive和nginx

配置keepalived实现nginx负载均衡的高可用

keepalive更适合于见得IP漂移，如果资源服务有控制，heartbeat更适合，比如存储方向的高可用

三、 nginx反向代理的健康检查

nginx做反向代理的时候，当后端就的服务器出现宕机的时候，ngixn不能把这台realserver剔除upstream的，所以还会把请求转发到后端的这台realserve上，虽然nginx可以在localtion中启用proxy_next_upstream来解决返回给客户的错误页面，但这个还会会把请求转发转给这台服务器，然后再转发别的服务器，这样就浪费了一次转发，借助淘宝团队开发的nginx模块nginx_upstream_check_module来检测后方的realserver的健康状态，如果后端服务器不可用，则所有的请求不转发到这台服务器

check interval=5000 rise=1 fall=3 timeout=4000;

3.1 直接添加到配置文件

[root@node2 ~]# vim /usr/local/nginx/conf/nginx.conf

worker_processes  1;
events {
    worker_connections  1024;
}
http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;
upstream  web_pools {
        server 172.25.254.134:80 weight=5;
        server 172.25.254.135:80 weight=5;
#       server 172.25.254.158:80 weight=5  backup;
check interval=5000 rise=1 fall=3 timeout=4000;

}
    server {
        listen       80;
        server_name  www.lbtest.com;
        location / {
           # root   html;
           # index  index.html index.htm;
            proxy_set_header Host $host;
            proxy_pass http://web_pools;
        }
    }
}

[root@node2 ~]# nginx -t

nginx: [emerg] unknown directive "check" in /usr/local/nginx/conf/nginx.conf:14
nginx: configuration file /usr/local/nginx/conf/nginx.conf test failed 

检查失败

下载nginx的模块https://github.com/yaoweibin/nginx_upstream_check_module，使用nginx打上模块的安装，当做nginx的升级

3.2 下载模块

[root@node2 nginx-1.12.2]# yum -y install git

[root@node2 nginx-1.12.2]#  git clone https://github.com/yaoweibin/nginx_upstream_check_module.git

[root@node2 nginx-1.12.2]# ll

drwxr-xr-x. 7 root   root     4096 Apr 13 00:57 nginx_upstream_check_module

[root@node2 nginx-1.12.2]# cd nginx_upstream_check_module/

[root@node2 nginx_upstream_check_module]# ll

-rw-r--r--. 1 root root      0 Apr 13 00:57 CHANGES
-rw-r--r--. 1 root root   7921 Apr 13 00:57 check_1.11.1+.patch
-rw-r--r--. 1 root root   8330 Apr 13 00:57 check_1.11.5+.patch
-rw-r--r--. 1 root root   8060 Apr 13 00:57 check_1.12.1+.patch
-rw-r--r--. 1 root root   8054 Apr 13 00:57 check_1.14.0+.patch
-rw-r--r--. 1 root root   5483 Apr 13 00:57 check_1.2.1.patch
-rw-r--r--. 1 root root   7130 Apr 13 00:57 check_1.2.2+.patch
-rw-r--r--. 1 root root   7094 Apr 13 00:57 check_1.2.6+.patch
-rw-r--r--. 1 root root   6791 Apr 13 00:57 check_1.5.12+.patch
-rw-r--r--. 1 root root   8295 Apr 13 00:57 check_1.7.2+.patch
-rw-r--r--. 1 root root   8346 Apr 13 00:57 check_1.7.5+.patch
-rw-r--r--. 1 root root   8509 Apr 13 00:57 check_1.9.2+.patch
-rw-r--r--. 1 root root   6943 Apr 13 00:57 check.patch
-rw-r--r--. 1 root root    749 Apr 13 00:57 config
drwxr-xr-x. 2 root root     43 Apr 13 00:57 doc
-rw-r--r--. 1 root root   1709 Apr 13 00:57 nginx-sticky-module.patch
drwxr-xr-x. 2 root root     29 Apr 13 00:57 nginx-tests
-rw-r--r--. 1 root root 112010 Apr 13 00:57 ngx_http_upstream_check_module.c
-rw-r--r--. 1 root root    529 Apr 13 00:57 ngx_http_upstream_check_module.h
-rw-r--r--. 1 root root   2848 Apr 13 00:57 ngx_http_upstream_jvm_route_module.patch
-rw-r--r--. 1 root root  11509 Apr 13 00:57 README
drwxr-xr-x. 6 root root     79 Apr 13 00:57 test
-rw-r--r--. 1 root root   3342 Apr 13 00:57 upstream_fair.patch
drwxr-xr-x. 2 root root     81 Apr 13 00:57 util

3.3 打补丁

[root@node2 nginx_upstream_check_module]# cd ../

[root@node2 nginx-1.12.2]# yum -y install patch

注：因nginx版本更新，1.12以上版本的nginx，补丁为check_1.11.5+.patch

[root@node2 nginx-1.12.2]# patch -p0 < ./nginx_upstream_check_module/check_1.11.5+.patch

patching file src/http/modules/ngx_http_upstream_hash_module.c
patching file src/http/modules/ngx_http_upstream_ip_hash_module.c
patching file src/http/modules/ngx_http_upstream_least_conn_module.c
patching file src/http/ngx_http_upstream_round_robin.c
patching file src/http/ngx_http_upstream_round_robin.h

3.4 编译安装

[root@node2 nginx-1.12.2]# ./configure --prefix=/usr/local/nginx \
> --user=nginx --group=nginx \
> --with-http_ssl_module \
> --with-http_realip_module \
> --with-http_addition_module \
> --with-http_gzip_static_module \
> --with-http_stub_status_module \
> --with-http_sub_module \
> --with-pcre \
> --add-module=./nginx_upstream_check_module

出现一个新的目录 为objs

[root@node2 nginx-1.12.2]# ll

drwxr-xr-x. 4 root   root      187 Apr 13 01:04 objs

[root@node2 nginx-1.12.2]# make

sed -e "s|%%PREFIX%%|/usr/local/nginx|" \
    -e "s|%%PID_PATH%%|/usr/local/nginx/logs/nginx.pid|" \
    -e "s|%%CONF_PATH%%|/usr/local/nginx/conf/nginx.conf|" \
    -e "s|%%ERROR_LOG_PATH%%|/usr/local/nginx/logs/error.log|" \
    < man/nginx.8 > objs/nginx.8
make[1]: Leaving directory `/usr/local/src/nginx-1.12.2'

[root@node2 nginx-1.12.2]# ll objs/

drwxr-xr-x. 3 root root      41 Apr 13 01:04 addon
-rw-r--r--. 1 root root   16895 Apr 13 01:04 autoconf.err
-rw-r--r--. 1 root root   42396 Apr 13 01:04 Makefile
-rwxr-xr-x. 1 root root 5993600 Apr 13 01:06 nginx   #nginx新的可执行文件
-rw-r--r--. 1 root root    5341 Apr 13 01:06 nginx.8
-rw-r--r--. 1 root root    7202 Apr 13 01:04 ngx_auto_config.h
-rw-r--r--. 1 root root     657 Apr 13 01:03 ngx_auto_headers.h
-rw-r--r--. 1 root root    6412 Apr 13 01:04 ngx_modules.c
-rw-r--r--. 1 root root   87120 Apr 13 01:06 ngx_modules.o
drwxr-xr-x. 9 root root      91 Apr  3 22:38 src

备份就得ngxin，并拷贝新的nginx

[root@node2 nginx-1.12.2]# cd /usr/local/nginx/sbin/

[root@node2 sbin]# mv nginx nginx.bak

[root@node2 sbin]# cp /usr/local/src/nginx-1.12.2/objs/nginx /usr/local/nginx/sbin

[root@node2 sbin]# /usr/local/nginx/sbin/nginx -s stop

nginx: [emerg] getpwnam("nginx") failed

[root@node2 sbin]# id nginx

id: nginx: no such user

[root@node2 sbin]# useradd nginx

[root@node2 sbin]# id nginx

uid=1002(nginx) gid=1002(nginx) groups=1002(nginx)

[root@node2 sbin]# /usr/local/nginx/sbin/nginx -s stop

[root@node2 sbin]# /usr/local/nginx/sbin/nginx 

[root@node2 ~]# 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

成功安装 

3.5 配置

worker_processes  1;
events {
    worker_connections  1024;
}
http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;
upstream  web_pools {
        server 172.25.254.134:80 weight=5;
        server 172.25.254.135:80 weight=5;
#       server 172.25.254.158:80 weight=5  backup;
check interval=5000 rise=1 fall=3 timeout=4000;

}
    server {
        listen       80;
        server_name  www.lbtest.com;
        location / {
            proxy_set_header Host $host;
            proxy_pass http://web_pools;
        }
        location /nstatus{
        check_status;
        access_log off;
        }
    }
}

 [root@node2 conf]# nginx -s reload

3.6 访问测试

两个状态正常

关掉一个

[root@web1 image]# systemctl stop httpd

 

关掉两个

[root@web2 ~]# systemctl stop httpd

开启一个

[root@web1 image]# systemctl start httpd

[root@web2 ~]# systemctl restart httpd

 

成功实现后端检查功能

参考：老男孩教育视频公开课https://www.bilibili.com/video/av25869969/?p=19