Nginx+tomcat realizes load balancing

Step 1: Install and configure nginx, please refer to: http://www.cnblogs.com/klslb/p/8962379.html

Step 2: Prepare three tomcats.

I have prepared three tomcats here and renamed them for easy distinction.

Modify each tomcat startup port. And keep in mind!

In order to distinguish which tomcat is, enter webapps\ROOT, and modify the title of index.jsp.

 

Step 3: Open the nginx installation directory, find nginx.conf in the conf directory, and replace all the following configuration files.

  1  #Users and groups used by Nginx, not specified under window 
   2  #user nobody;
   3  
  4 #Number  of working child processes (usually equal to the number of CPUs or twice as many as CPUs)  
   5  worker_processes 4;
   6  
  7 #Error  log storage path 
   8  #error_log logs/error.log;
   9  #error_log logs/error.log notice;
 10  error_log logs/error.log info;
 11  
12 #Specify  pid storage file  
 13  #pid logs/nginx.pid;
 14  
15  
16  events {
 17 #Maximum      allowed Number of connections
 18      worker_connections 1024;
 19  
20  }
 21  
22  
23 http {
 24     include       mime.types;
 25     default_type  application/octet-stream;
 26 
 27     access_log  logs/access.log;
 28     client_header_timeout  3m;  
 29     client_body_timeout    3m;  
 30     send_timeout           3m;  
 31 
 32     client_header_buffer_size    1k;  
 33     large_client_header_buffers  4 4k;  
 34 
 35     sendfile        on;  
 36     tcp_nopush      on;  
 37     tcp_nodelay     on;
 38 
 39     # 配置负载均衡
 40     upstream localhost{
41          #How does Nginx achieve load balancing? The upstream of Nginx currently supports the following distribution methods
 42 #1, polling (default)
 43 #Each request is allocated to different back-end servers one by one in chronological order. If the back-end server goes down, it can be automatically eliminated.
 44         #2、weight
 45 #Specify the polling probability, the weight is proportional to the access ratio, and it is used in the case of uneven performance of the backend server.
 46         #2、ip_hash
 47 #Each request is allocated according to the hash result of the access ip, so that each visitor fixedly accesses a backend server, which can solve the problem of session.
 48 #3, fair (third party)
 49 #Allocate requests according to the response time of the backend server, and assign priority to those with short response time.
 50 #4. url_hash (third party)
 51 #Assign requests according to the hash result of accessing the url, so that each url is directed to the same back-end server, which is more effective when the back-end server is cached.  
 52         ip_hash;

 
 53 　　　　　#本机IP+三个tomcat端口号 54        　server 192.168.12.209:8081 weight=1; 
 55          server 192.168.12.209:8082 weight=2;  
 56          server 192.168.12.209:8083 weight=3; 
 57    }
 58 59    server {
 60        listen       80;
 61        server_name  localhost;
 62 63        #charset koi8-r;
 64 65        #access_log  logs/host.access.log  main;
 66 67        location / {
 68            root   html;
 69　
     
    
  
  
               index index.html index.htm;
 70              proxy_connect_timeout 3; #nginx connects to the back-end server connection timeout (proxy connection timeout) 
 71                proxy_send_timeout 30; #back-end server data return time (proxy send timeout) 
 72                 proxy_read_timeout 30; #connection is successful 73                 proxy_pass http://localhost;
 74          }
 75          
76          #error_page 404 /404.html;
 77 
 78  
#          redirect server error pages to the static page /50x.html
 79          #
 80          error_page 500 502 503 504 /50x.html;
 81          location = /50x.html {
 82             root   html;
 83         }
 84 
 85         # proxy the PHP scripts to Apache listening on 127.0.0.1:80
 86         #
 87         #location ~ \.php$ {
 88         #    proxy_pass   http://127.0.0.1;
 89         #}
 90 
 91         # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
 92         #
 93         #location ~ \.php$ {
 94         #    root           html;
 95         #    fastcgi_pass   127.0.0.1:9000;
 96         #    fastcgi_index  index.php;
 97         #    fastcgi_param  SCRIPT_FILENAME  /scripts$fastcgi_script_name;
 98         #    include        fastcgi_params;
 99         #}
100 
101         # deny access to .htaccess files, if Apache's document root
102         # concurs with nginx's one
103         #
104         #location ~ /\.ht {
105         #    deny  all;
106         #}
107     }
108 
109 
110     # another virtual host using mix of IP-, name-, and port-based configuration
111     #
112     #server {
113     #    listen       8000;
114     #    listen       somename:8080;
115     #    server_name  somename  alias  another.alias;
116 
117     #    location / {
118     #        root   html;
119     #        index  index.html index.htm;
120     #    }
121     #}
122 
123 
124     # HTTPS server
125     #
126     #server {
127     #    listen       443 ssl;
128     #    server_name  localhost;
129 
130     #    ssl_certificate      cert.pem;
131     #    ssl_certificate_key  cert.key;
132 
133     #    ssl_session_cache    shared:SSL:1m;
134     #    ssl_session_timeout  5m;
135 
136     #    ssl_ciphers  HIGH:!aNULL:!MD5;
137     #    ssl_prefer_server_ciphers  on;
138 
139     #    location / {
140     #        root   html;
141     #        index  index.html index.htm;
142     #    }
143     #}
144 
145 }

 

Step 4: Start three tomcats respectively. Restart nginx. Browser access localhost. (Startup command: nginx -s reload)

It can be seen that three tomcats are randomly accessed, and the weight can be configured to specify the polling probability. The weight is proportional to the access ratio, which is used when the performance of the backend server is uneven. priority access