The Haproxy of the enterprise

Haproxy is a powerful, flexible and easy to use reverse proxy software, provides a high-availability, load-balanced, back-end server Agent functions, it is in the 7-tier load balancing function is very powerful (support cookie track, header rewrite, etc.), support dual-machine hot standby, support virtual host , has a very good server health check function, when its agent's back-end server failure, Haproxy will automatically remove the server, after the failure to automatically join the server, but also provide an intuitive monitoring page, you can clearly monitor the health of the service cluster in real-time.

Software that implements load balancing on layer four (TCP):
LVS------> Heavy-weight
Nginx------> Lightweight, with cache function, regular expression more flexible
Haproxy------> Analog four-layer forwarding, more flexible
Software that implements reverse proxy on Layer seven (HTTP):
Haproxy------> Natural skills, full support seven Layer agent, session hold, tag, path transfer;
Nginx------> only in the HTTP protocol and the Mail protocol function better, the performance is similar to Haproxy;
Apache------> Poor functionality

The Haproxy configuration file is divided into four sections:
Global configuration:
Global: Configuration Segment
Agent configuration:
Default: Defaults configuration-----> All the same content in backend, frontend, Linsten can be defined here;
Frontend: Previous Configuration-----> Define front End sockets, accept client requests;
Backend: Backend Configuration-----> Define back-end allocation rules, interacting with backend servers;
Listen: Binding configuration-----> binds the specified client directly to the backend-specific server;

Experimental environment: rhel6.5 SELinux and iptables disabled
172.25.85.2 server2.example.com
172.25.85.3 server3.example.com

172.25.85.7 server7.example.com

172.25.85.8 server8.example.com

Installation and configuration of 1.haproxy:
Install on Server3 and Server2:
Yum Install Haproxy-y
/etc/init.d/haproxy start

on the Server2:
Vim/etc/haproxy/haproxy.cfg

You need to comment out a portion:
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Stats Uri/statusstats Auth Admin:westos

frontend  westos *:80           default_backend   webbackend  web            balance roundrobin            server  web1 172.25.31.10:80 check  weight 1            server  web2 172.25.31.11:80  check  weight  1             server backup   127.0.0.1:8080  backup            server backup 127.0.0.1:8080 backup 

/etc/init.d/haproxy Reload



Detection:
Open the httpd on Server7 and Server8:

Open 172.25.85.2 in the browser
Alternate appearance of server7.linux.org server8.westos.org

Open 172.25.85.2/status in the browser

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Detection 2:
close the httpd on Server7 and Server8
on the Server2:
echo server2.zhangweijing > index.html
Vim/etc/httpd/conf/httpd.conf

Listen 8080

/ETC/INIT.D/HTTPD start


Open in Browser 172.25.85.2:
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2. Server2:
Tail-f/var/log/messages
Vim/etc/rsyslog.conf

$ModLoad Imudp$udpserverrun 514

local2.*/var/log/haproxy.log

/etc/init.d/rsyslog Reload
Tail-f/var/log/messages
Tail-f/var/log/haproxy.log





3. Server2:
Vim/etc/haproxy/haproxy.cfg

Add Stats auth Admin:westos/etc/init.d/haproxy reload

Open 172.25.85.2/status in the browser


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4.1 Server2:
Vim/etc/haproxy/haproxy.cfg

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Increase

frontend westos *:80         acl bad src 172.25.85.250        block if  bad        errorloc  403      http://172.25.85.2:8080        default_backend webbackend  web          balance roundrobin           server  web1 172.25.85.7:80 check           server  web2 172.25.85.8:80 check           server backup 127.0.0.1:8080 backup 

/etc/init.d/haproxy Reload

Open http://172.25.85.2:8080/in the browser
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4.2 Server2:

Vim/etc/haproxy/haproxy.cfg

frontend westos *:80        acl bad src 172.25.85.250       #block  if bad        #errorloc   403     http://172.25.85.2:8080         redirect location http://172.25.85.3:80 if  bad        default_backend webbackend web           balance roundrobin           server  web1 172.25.85.7:80 check           server  web2 172.25.85.8:80 check          server backup 127.0.0.1:8080 backup 

/etc/init.d/haproxy Reload
Open http://172.25.85.3 in the browser
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4.3 Server2:

Vim/etc/haproxy/haproxy.cfg
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frontend westos *:80        acl bad src  172.25.85.250              #block  if  bad       #errorloc   403     http:// 172.25.85.2:8080       #redirect  location http://172.25.85.3:80 if  bad      # http-request deny if denyfile bad        default_backend webbackend web           balance roundrobin           server  web1 172.25.85.7:80 check           server  web2 172.25.85.8:80 check          server backup 127.0.0.1:8080 backup 

    /etc/init.d/haproxy Reload

     in Server7:
    cd/var/www/html/
    mkdir admin
    CD admin/
     echo server7.server7 > index.html



    at Server8:
    cd/var/www/html/
    mkdir admin
    CD admin/
     echo server8.server8 > index.html

     Open in Browser http://172.25.85.2 /admin/
    alternating server7.server7 server8.server8



4.4 server2:
    vim/etc/haproxy/haproxy.cfg

frontend westos *:80        acl bad src  172.25.85.250        acl denyfile path /admin/        #block  if bad       #errorloc    403     http://172.25.85.2:8080       #redirect   Location http://172.25.85.3:80 if bad      http-request deny  if denyfile bad        default_backend webbackend  web          balance roundrobin           server  web1 172.25.85.7:80 check           server  web2 172.25.85.8:80 check      &nbSp;   server backup 127.0.0.1:8080 backup 

 
       /etc/init.d/haproxy reload
 

       Open http://172.25.85.2/admin/
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5. Server2:
        vim/etc/haproxy/haproxy.cfg

frontend westos *:80        acl bad src  172.25.85.250        acl denyfile path /admin/        #block  if bad       #errorloc    403     http://172.25.85.2:8080       #redirect   location http://172.25.85.3:80 if bad       #http-request  deny if denyfile bad       acl url_static        path_beg       -i   /static   /images /javascript /stylesheets       acl url_ Static       path_end       -i .jpg  .gif .png .css .js       use_backend images    if url_ Static        default_backend  upload

Backend images Balance Roundrobin server web1 172.25.85.7:80 Check server backup 127.0.0.1:80 Backup

Backend Upload server web2 172.25.85.8:80 check

        /etc/init.d/haproxy Reload




     server7:
    
    cd/var/www/html/
     MkDir images             # # Give this directory a small picture redhat.jpg
    
 
   Open in Browser: http://172.25.85.2/images/ Redhat.jpg
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6.server2:
  vim/etc/haproxy/haproxy.cfg
   

frontend westos *:80        acl bad src  172.25.85.250        acl denyfile path /admin/        #block  if bad       #errorloc    403     http://172.25.85.2:8080       #redirect   location http://172.25.85.3:80 if bad       #http-request  deny if denyfile bad       acl url_static        path_beg       -i   /static   /images /javascript /stylesheets       acl url_ Static       path_end       -i .jpg  .gif .png .css .js     acl read method get     acl  read method  HEAD     acl write method PUT      acl write method  post#     use_backend  images    if url_static#        use_ backend images if read        use_backend   upload  if write        default_backend   Images

Backend images Balance Roundrobin server Web1 172.25.85.8:80 Check

Backend Upload server web1 172.25.85.7:80 check

/etc/init.d/haproxy Reload


in Server8:
Cd/var/www/html # #将upload文件放在这个目录下
Chown 777 Upload

Cd/var/www/html/upload

mkdir Upload

You can upload files by opening 172.25.85.2/upload in your browser.

The Haproxy of the enterprise