Catalog

* Case environment

* build Nginx1

* build Nginx2

* Compilation and installation Haproxy

* install keepalived

* Case test

*Haproxy journal

*Haproxy Parameter optimization of

        Haproxy It is a popular cluster scheduling tool , There are many similar cluster scheduling tools , Such as LVS and Nginx. By comparison ,LVS Best performance , But the construction is relatively complex ;Nginx Of upstream Module supports clustering , However, the health check function of cluster nodes is not strong , No performance Haproxy good .Haproxy The official website is http://www.haproxy.org/.

Case pre knowledge points

1. HTTP request Request mode GET The way POST The way Return status code The normal status code is 2××、3×× The abnormal status code is 4××、5××

2. Common scheduling algorithms for load balancing

   RR（Round Robin）： Polling scheduling ​ LC（Least Connections）： Minimum connections ​ SH（Source Hashing）： Source based access scheduling

Case environment

         The goal of the experiment ： Use haproxy build web to cluster around , Achieve load balancing and high availability , Use keepalived+haproxy Realize dual machine hot standby and load balancing .

         Case preparation ： Configure according to the following figure IP Address , The drift address is 192.168.1.100, Turn off firewall 、selinux、 build yum Warehouse .

build Nginx1

[[email protected] ~]# yum -y install pcre-devel zlib-devel
[[email protected] ~]# useradd -M -s /sbin/nologin nginx
[[email protected] ~]# eject
[[email protected] ~]# mount /dev/cdrom /media
mount: /dev/sr0 is write-protected, mounting read-only
[[email protected] ~]# tar zxf /media/nginx-1.12.0.tar.gz -C /usr/src
[[email protected] ~]# cd /usr/src/nginx-1.12.0/
[[email protected] nginx-1.12.0]# ./configure --prefix=/usr/local/nginx --user=nginx --group=nginx
[[email protected] nginx-1.12.0]# make && make install

The default information after installation is as follows .

Default installation directory ：/usr/local/nginx

The default log ：/usr/local/nginx/logs

Listening port ：80

Default web Catalog ：/usr/local/nginx/html

[[email protected] nginx-1.12.0]# cd /usr/local/nginx/html/
[[email protected] html]# echo 111111 > test.html                              // Create a test page 
[[email protected] html]# /usr/local/nginx/sbin/nginx                          // start-up Nginx
[[email protected] html]# netstat -anpt | grep nginx
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      6762/nginx: master  

After installation , Client access http://192.168.1.20/test.html test .

build Nginx2

The steps of compiling and installing are the same as Nginx1 identical , The difference lies in the test web page .

[[email protected] html]# echo 22222 > test.html

After installation , Client access http://192.168.1.30/test.html test .

Compilation and installation Haproxy

[[email protected] ~]# yum -y install pcre-devel bzip2-devel 
[[email protected] ~]# eject
[[email protected] ~]# mount /dev/cdrom /media/
mount: /dev/sr0 is write-protected, mounting read-only
[[email protected] ~]# tar zxf /media/haproxy-1.5.19.tar.gz -C /usr/src
[[email protected] ~]# cd /usr/src/haproxy-1.5.19/
[[email protected] haproxy-1.5.19]# make TARGET=linux26                    //64 Bit system 
[[email protected] haproxy-1.5.19]# make install

Haproxy Server configuration

• Build profile

[[email protected] haproxy-1.5.19]# mkdir /etc/haproxy                             // Create a directory of configuration files 
[[email protected] haproxy-1.5.19]# cp examples/haproxy.cfg /etc/haproxy/          // take haproxy.cfg Copy the file to the configuration file directory 

• Haproxy Configuration item introduction

        Haproxy The configuration file is usually divided into three parts , namely global、defaults and listen.global Configure for global ,defaults For default configuration ,listen Configure... For application components .

global The configuration items are described as follows ：

global
        log 127.0.0.1   local0                      // Configure logging ,local0 For log devices , It is stored in the system log by default 
        log 127.0.0.1   local1 notice               //notice For log level , Usually there are 24 A level 
        maxconn 4096                                // maximum connection 
        uid 99                                      // user uid
        gid 99                                      // user gid

defaults The configuration items are described as follows ：

defaults
        log     global                              // Define the log as global Log definition in configuration 
        mode    http                                // The model is http
        option  httplog                             // use http Log format log 
        retries 3                                   // Check node server failures , Continuous over 3 Secondary failure , The node is considered unavailable 
        redispatch                                  // When the server load is high , Automatically end connections that have been queued for a long time 
        maxconn 2000                                // maximum connection 
        contimeout      5000                        // Connection timeout 
        clitimeout      50000                       // Client timeout 
        srvtimeout      50000                       // Server timeout 

global The configuration items are described as follows ：

listen  appli4-backup 0.0.0.0:10004                                                 // Define a appli4-backup Application 
        option  httpchk /index.html                                                 // Check the... Of the server index.html file 
        option  persist                                                             // Force the request to be sent to already down Dropped servers 
        balance roundrobin                                                          // The load balancing scheduling algorithm uses the polling algorithm 
        server  inst1 192.168.114.56:80 check inter 2000 fall 3                     // Define online nodes 
        server  inst2 192.168.114.56:81 check inter 2000 fall 3 backup              // Define backup nodes 

• According to the current cluster design , take haproxy.conf The content of the configuration file is modified as follows .

[[email protected] ~]# vim /etc/haproxy/haproxy.cfg
# this config needs haproxy-1.1.28 or haproxy-1.2.1
​
global
        log 127.0.0.1   local0
        log 127.0.0.1   local1 notice
        #log loghost    local0 info
        maxconn 4096
        #chroot /usr/share/haproxy                                      // Comment out 
        uid 99
        gid 99
        daemon
        #debug
        #quiet
​
defaults
        log     global
        mode    http
        option  httplog
        option  dontlognull
        retries 3
        #redispatch                                                     // Comment out 
        maxconn 2000
        contimeout      5000
        clitimeout      50000
        srvtimeout      50000
listen  appli4-backup 0.0.0.0:80                                        // Copy listen Configuration item module content , Change the port number to 80
        option  httpchk GET /index.html                                 //http The request method is changed to GET
        balance roundrobin
        server  inst1 192.168.1.20:80 check inter 2000 fall 3           // Configuration of two node servers 
        server  inst2 192.168.1.30:80 check inter 2000 fall 3           // Delete all the following configurations in the configuration file 

• Create a self starting script

[[email protected] ~]# cp /usr/src/haproxy-1.5.19/examples/haproxy.init /etc/init.d/haproxy
[[email protected] ~]# ln -s /usr/local/sbin/haproxy /usr/sbin/haproxy
[[email protected] ~]# chmod +x /etc/init.d/haproxy 
[[email protected] ~]# chkconfig --add /etc/init.d/haproxy 
[[email protected] ~]# /etc/init.d/haproxy start
Starting haproxy (via systemctl):                          [  OK  ]

install keepalived

• install ipvsadm and keepalived package .

[[email protected] ~]# mount /dev/cdrom /media
mount: /dev/sr0 is write-protected, mounting read-only
[[email protected] ~]# yum -y install ipvsadm keepalived

• To configure keepalived.cof

         do haproxy+keepalived to cluster around , You only need to configure and modify the hot standby instance , Specify the primary and standby schedulers , name ,VIP Address , Priority and drift address are enough .

[[email protected] ~]# vim /etc/keepalived/keepalived.conf 
! Configuration File for keepalived
​
global_defs {
......// Omit part 
    router_id R1                    // Name of main regulator 
}  
​
vrrp_instance VI_1 {
    state MASTER                    // Hot standby state 
    interface ens33                 //VIP Address physical interface 
    virtual_router_id 51
    priority 100                    // priority 
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.1.100               // Drift address 
    }
}
[[email protected] ~]# systemctl start keepalived
[[email protected] ~]# systemctl enable keepalived

        Haproxy+keepalived The installation configuration of the backup scheduler is roughly the same , The only thing to notice is that keepalived When the configuration , Distinguish the main 、 Standby scheduler configuration （ Specify the primary and standby schedulers , name ,VIP Address , Priority and drift address ）. Continue to configure according to the above configuration haproxy2+keepalived2.

Case test

• The client opens the browser to access http://192.168.1.100/test.html, Refresh the browser twice to view the web content and test the load balance （ You should see 11111 and 22222 Two web pages ）. To break off web1, Refresh twice in access to test high availability （ At this time, only 22222）.

• broken keepalived Master tuner network , Continue to visit http://192.168.1.100/test.html, Successful access means keepalived Load balancing successful （ You should see 11111 and 22222 Two web pages ）.

Haproxy journal

         Modify the log configuration options in the original configuration file , stay global Configuration in the project . Save and restart after modifying the configuration Haproxy.

[[email protected] ~]# vim /etc/haproxy/haproxy.cfg
        log /dev/log    local0 info
        log /dev/log    local0 notice
[[email protected] ~]# /etc/init.d/haproxy restart             // restart 
Restarting haproxy (via systemctl):                        [  OK  ]

         For ease of management , take Haproxy The relevant configuration is defined independently to haproxy.conf And on the /etc/rsyslog.d/ Next ,rsyslog All configuration files in this directory will be loaded automatically at startup .

[[email protected] ~]# vim /etc/rsyslog.d/haproxy.conf
if ($programname == 'haproxy' and $syslogseverity-text == 'info') then -/var/log/haproxy/haproxy-info.log
& ~ 
if ($programname == 'haproxy' and $syslogseverity-text == 'notice') then -/var/log/haproxy/haproxy-notice.log
& ~
[[email protected] ~]# systemctl restart rsyslog

After client access , You can use the following command to check in time Haproxy Access request log information for .

[[email protected] ~]# tail -f /var/log/haproxy/haproxy-info.log
Jul 23 23:08:35 localhost haproxy[43674]: 192.168.1.200:62207 [23/Jul/2022:23:08:35.157] appli4-backup appli4-backup/inst2 0/0/1/1/2 200 240 - - ---- 1/1/0/1/0 0/0 "GET /test.html HTTP/1.1"
Jul 23 23:08:35 localhost haproxy[43674]: 192.168.1.200:62207 [23/Jul/2022:23:08:35.159] appli4-backup appli4-backup/inst1 198/0/5/1/204 200 241 - - ---- 2/2/0/1/0 0/0 "GET /test.html HTTP/1.1"

Haproxy Parameter optimization of