一、引言

1.1 代理問題

客戶端到底要將請(qǐng)求發(fā)送給哪臺(tái)服務(wù)器胚鸯。

發(fā)送給服務(wù)器1還是服務(wù)器2
image.png

1.2 負(fù)載均衡問題

如果所有客戶端的請(qǐng)求都發(fā)送給了服務(wù)器1玄渗，那么服務(wù)器2將沒有任何意義

負(fù)載均衡問題
image.png

1.3 資源優(yōu)化

客戶端發(fā)送的請(qǐng)求可能是申請(qǐng)動(dòng)態(tài)資源的，也有申請(qǐng)靜態(tài)資源仪媒，但是都是去Tomcat中獲取的

靜態(tài)資源訪問
image.png

1.4 Nginx處理

在搭建集群后沉桌，使用Nginx
image.png

二、Nginx概述

Nginx是由俄羅斯人研發(fā)的算吩，應(yīng)對(duì)Rambler的網(wǎng)站留凭，并且2004年發(fā)布的第一個(gè)版本。

Nginx之父
image.png

Nginx的特點(diǎn)：

• 穩(wěn)定性極強(qiáng)偎巢。 7*24小時(shí)不間斷運(yùn)行蔼夜。
• Nginx提供了非常豐富的配置實(shí)例。
• 占用內(nèi)存小压昼，并發(fā)能力強(qiáng)求冷。

三、Nginx的安裝

3.1 安裝Nginx

使用Docker-Compose安裝窍霞，創(chuàng)建docker-compose.yml寫入以下內(nèi)容：

version: '3.1'
services:
  nginx:
    restart: always
    image: daocloud.io/library/nginx:latest
    container_name: nginx
    ports:
      - 80:80

[root@iz8vbdmrir2n6xqzrbd93hz ~]# cd /opt
[root@iz8vbdmrir2n6xqzrbd93hz opt]# ls
containerd  docker_mysql_tomcat  docker_ssm  yangl
[root@iz8vbdmrir2n6xqzrbd93hz opt]# mkdir docker_nginx
[root@iz8vbdmrir2n6xqzrbd93hz opt]# cd docker_nginx/
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# vim docker-compose.yml
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# docker-compose-Linux-x86_64 up -d
Creating network "docker_nginx_default" with the default driver
Pulling nginx (daocloud.io/library/nginx:latest)...
latest: Pulling from library/nginx
6ec8c9369e08: Pull complete
d3cb09a117e5: Pull complete
7ef2f1459687: Pull complete
e4d1bf8c9482: Pull complete
795301d236d7: Pull complete
Digest: sha256:deb724a427ea79face617392a5a471fdcb4cdb57f971ee6b7e492b90fecb199f
Status: Downloaded newer image for daocloud.io/library/nginx:latest
Creating nginx ... done

測(cè)試：瀏覽器訪問即可（80端口可以省略不寫匠题，云服務(wù)器記得去開放80端口）

3.2 Nginx的配置文件

關(guān)于Nginx的核心配置文件nginx.conf

[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# docker ps
CONTAINER ID        IMAGE                                    COMMAND                  CREATED             STATUS              PORTS                    NAMES
4d8af14af5cb        daocloud.io/library/nginx:latest         "/docker-entrypoint.…"   6 minutes ago       Up 6 minutes        0.0.0.0:80->80/tcp       nginx
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# docker exec -it 4d8 bash
root@4d8af14af5cb:/# cd /etc/nginx
root@4d8af14af5cb:/etc/nginx# ls
conf.d  fastcgi_params  koi-utf  koi-win  mime.types  modules  nginx.conf  scgi_params  uwsgi_params  win-utf
root@4d8af14af5cb:/etc/nginx# cat nginx.conf 

user  nginx;
worker_processes  1;

error_log  /var/log/nginx/error.log warn;
pid        /var/run/nginx.pid;

# 參數(shù)說明
# 以上統(tǒng)稱為全局塊， 
# worker_processes的數(shù)值越大但金，Nginx的并發(fā)能力就越強(qiáng)（由運(yùn)維人員修改）
# error_log 代表Nginx的錯(cuò)誤日志存放的位置

events {
    worker_connections  1024;
}

# 參數(shù)說明
# events塊
# worker_connections的數(shù)值越大韭山，Nginx的并發(fā)能力就越強(qiáng)（由運(yùn)維人員修改）

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    sendfile        on;
    #tcp_nopush     on;

    keepalive_timeout  65;

    #gzip  on;

    include /etc/nginx/conf.d/*.conf;
}

# 參數(shù)說明
# http塊
# include代表引入一個(gè)外部的文件 -> /mime.types中放著大量的媒體類型
# include /etc/nginx/conf.d/*.conf; -> 引入了conf.d目錄下的以.conf為結(jié)尾的配置文件

root@4d8af14af5cb:/etc/nginx# ls
conf.d  fastcgi_params  koi-utf  koi-win  mime.types  modules  nginx.conf  scgi_params  uwsgi_params  win-utf
root@4d8af14af5cb:/etc/nginx# cd conf.d/
root@4d8af14af5cb:/etc/nginx/conf.d# ls
default.conf
root@4d8af14af5cb:/etc/nginx/conf.d# cat default.conf 

# 參數(shù)說明
# server塊
# listen： 代表Nginx監(jiān)聽的端口號(hào)
# localhost：代表Nginx接收請(qǐng)求的ip

server {
    listen       80;
    listen  [::]:80;
    server_name  localhost;

    #charset koi8-r;
    #access_log  /var/log/nginx/host.access.log  main;

    location / {
        root   /usr/share/nginx/html;
        index  index.html index.htm;
    }
    
    # 參數(shù)說明
    # location塊
    # root：將接收到的請(qǐng)求根據(jù)/usr/share/nginx/html去查找靜態(tài)資源
    # index： 默認(rèn)去上述的路徑中找到index.html或者index.htm

    #error_page  404              /404.html;

    # redirect server error pages to the static page /50x.html
    #
    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   /usr/share/nginx/html;
    }

    # proxy the PHP scripts to Apache listening on 127.0.0.1:80
    #
    #location ~ \.php$ {
    #    proxy_pass   http://127.0.0.1;
    #}

    # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
    #
    #location ~ \.php$ {
    #    root           html;
    #    fastcgi_pass   127.0.0.1:9000;
    #    fastcgi_index  index.php;
    #    fastcgi_param  SCRIPT_FILENAME  /scripts$fastcgi_script_name;
    #    include        fastcgi_params;
    #}

    # deny access to .htaccess files, if Apache's document root
    # concurs with nginx's one
    #
    #location ~ /\.ht {
    #    deny  all;
    #}
}

3.3 修改docker-compose文件

為了方便修改Nginx配置，修改docker-compose.yml文件冷溃，設(shè)置 volumes 钱磅，重新啟動(dòng)

version: '3.1'
services:
  nginx:
    restart: always
    image: daocloud.io/library/nginx:latest
    container_name: nginx
    ports:
      - 80:80
    volumes:
      - /opt/docker_nginx/conf.d/:/etc/nginx/conf.d

root@4d8af14af5cb:/etc/nginx/conf.d# exit
exit
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# ls
docker-compose.yml
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# docker-compose-Linux-x86_64 down
Stopping nginx ... done
Removing nginx ... done
Removing network docker_nginx_default
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# vim docker-compose.yml
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# docker-compose-Linux-x86_64 build
nginx uses an image, skipping
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# docker-compose-Linux-x86_64 up -d
Creating network "docker_nginx_default" with the default driver
Creating nginx ... done
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# ls
conf.d  docker-compose.yml

此時(shí)再使用瀏覽器訪問則無(wú)法訪問nginx.html頁(yè)面了，此時(shí)需要在conf.d目錄下創(chuàng)建default.conf文件似枕，配置一個(gè)server盖淡，再重新啟動(dòng)即可

server {
    listen       80;
    listen  [::]:80;
    server_name  localhost;

    location / {
        root   /usr/share/nginx/html;
        index  index.html index.htm;
    }
}

[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# cd conf.d/
[root@iz8vbdmrir2n6xqzrbd93hz conf.d]# ls
[root@iz8vbdmrir2n6xqzrbd93hz conf.d]# vim default.conf
[root@iz8vbdmrir2n6xqzrbd93hz conf.d]# cd ..
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# docker-compose-Linux-x86_64 restart
Restarting nginx ... done

四、Nginx的反向代理【重點(diǎn)】

4.1 正向代理和反向代理介紹

正向代理：

• 正向代理服務(wù)是由客戶端設(shè)立的菠净。
• 客戶端了解代理服務(wù)器和目標(biāo)服務(wù)器都是誰(shuí)禁舷。
• 幫助咱們實(shí)現(xiàn)突破訪問權(quán)限彪杉，提高訪問的速度，對(duì)目標(biāo)服務(wù)器隱藏客戶端的ip地址牵咙。

正向代理
image.png

反向代理：

• 反向代理服務(wù)器是配置在服務(wù)端的派近。
• 客戶端是不知道訪問的到底是哪一臺(tái)服務(wù)器。
• 達(dá)到負(fù)載均衡洁桌，并且可以隱藏服務(wù)器真正的ip地址渴丸。

image.png

4.2 基于Nginx實(shí)現(xiàn)反向代理

準(zhǔn)備一個(gè)目標(biāo)服務(wù)器，啟動(dòng)了之前的tomcat服務(wù)器另凌，使其能夠訪問到頁(yè)面

[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# docker ps
CONTAINER ID        IMAGE                              COMMAND                  CREATED             STATUS              PORTS                NAMES
818cd6a46ecb        daocloud.io/library/nginx:latest   "/docker-entrypoint.…"   3 hours ago         Up 40 minutes       0.0.0.0:80->80/tcp   nginx
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# cd ..
[root@iz8vbdmrir2n6xqzrbd93hz opt]# ls
containerd  docker_mysql_tomcat  docker_nginx  docker_ssm  yangl
[root@iz8vbdmrir2n6xqzrbd93hz opt]# cd docker_mysql_tomcat/
[root@iz8vbdmrir2n6xqzrbd93hz docker_mysql_tomcat]# ls
docker-compose.yml  mysql_data  tomcat_logs  tomcat_webapps
[root@iz8vbdmrir2n6xqzrbd93hz docker_mysql_tomcat]# cd tomcat_webapps/
[root@iz8vbdmrir2n6xqzrbd93hz tomcat_webapps]# ls
[root@iz8vbdmrir2n6xqzrbd93hz tomcat_webapps]# mkdir ROOT
[root@iz8vbdmrir2n6xqzrbd93hz tomcat_webapps]# cd ROOT/
[root@iz8vbdmrir2n6xqzrbd93hz ROOT]# vim index.html
[root@iz8vbdmrir2n6xqzrbd93hz ROOT]# cd ..
[root@iz8vbdmrir2n6xqzrbd93hz tomcat_webapps]# cd ..
[root@iz8vbdmrir2n6xqzrbd93hz docker_mysql_tomcat]# docker-compose-Linux-x86_64 up -d
Starting tomcat ... done
Starting mysql  ... done

然后修改nginx的default.conf配置文件谱轨，使其通過Nginx訪問到tomcat服務(wù)器。

server {
    listen       80;
    listen  [::]:80;
    server_name  localhost;

    # 基于反向代理訪問到Tomcat服務(wù)器
    location / {
      proxy_pass http://39.98.132.196:8080/;
    }
}

[root@iz8vbdmrir2n6xqzrbd93hz docker_mysql_tomcat]# cd ..
[root@iz8vbdmrir2n6xqzrbd93hz opt]# ls
containerd  docker_mysql_tomcat  docker_nginx  docker_ssm  yangl
[root@iz8vbdmrir2n6xqzrbd93hz opt]# cd docker_nginx/
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# ls
conf.d  docker-compose.yml
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# cd conf.d/
[root@iz8vbdmrir2n6xqzrbd93hz conf.d]# ls
default.conf
[root@iz8vbdmrir2n6xqzrbd93hz conf.d]# vim default.conf 
[root@iz8vbdmrir2n6xqzrbd93hz docker_nginx]# docker-compose-Linux-x86_64 restart
Restarting nginx ... done

4.3 關(guān)于Nginx的location路徑映射

優(yōu)先級(jí)關(guān)系如下：

# 1. 直接匹配
location = / {
  # 精準(zhǔn)匹配吠谢，主機(jī)名后面不能帶任何的字符串
}

# 2. 通用匹配
location /xxx {
  # 匹配所有以/xxx開頭的路徑
}

# 3. 正則匹配
location ~ /xxx {
  # 匹配所有以/xxx開頭的路徑
}

# 4. 匹配開頭路徑
location ^~ /images/ {
  # 匹配所有以/images開頭的路徑
}

# 5. 匹配后綴
location ~* \.(gif|jpg|png)$ {
  # 匹配以gif或者jpg或者png為結(jié)尾的路徑
}

# 6. 全部通配
location / {
  # 匹配全部路徑  
}