1. haproxy簡介

HAProxy是法國開發者 威利塔羅(Willy Tarreau) 在2000年使用C語言開發的一個開源軟體，是一款具備高并發(一萬以上)、高性能的TCP和HTTP負載均衡器，支持基于cookie的持久性，自動故障切換，支持正則運算式及web狀態統計，目前最新TLS版本為9.0

HAProxy是一個使用C語言撰寫的自由及開放源代碼軟體，其提供高可用性、負載均衡，以及基于TCP和HTTP的應用程式代理，

HAProxy是一個免費的負載均衡軟體，可以運行于大部分主流的Linux作業系統上，

HAProxy提供了L4(TCP)和L7(HTTP)兩種負載均衡能力，具備豐富的功能，HAProxy的社區非常活躍，版本更新快速，最關鍵的是，HAProxy具備媲美商用負載均衡器的性能和穩定性，

因為HAProxy的上述優點，它當前不僅僅是免費負載均衡軟體的首選，更幾乎成為了唯一選擇，

1.1 核心功能

• 負載均衡：L4和L7兩種模式，支持RR/靜態RR/LC/IP Hash/URI Hash/URL_PARAM Hash/HTTP_HEADER Hash等豐富的負載均衡演算法
• 健康檢查：支持TCP和HTTP兩種健康檢查模式
• 會話保持：對于未實作會話共享的應用集群，可通過Insert Cookie/Rewrite Cookie/Prefix Cookie，以及上述的多種Hash方式實作會話保持
• SSL：HAProxy可以決議HTTPS協議，并能夠將請求解密為HTTP后向后端傳輸
• HTTP請求重寫與重定向
• 監控與統計：HAProxy提供了基于Web的統計資訊頁面，展現健康狀態和流量資料，基于此功能，使用者可以開發監控程式來監控HAProxy的狀態

1.2 haproxy的關鍵特性

• 高性能
  通常情況下，HAProxy自身只占用15%的處理時間，剩余的85%都是在系統內核層完成的
• 高穩定性
  一旦成功啟動，除非作業系統或硬體故障，否則就不會崩潰

2. haproxy部署安裝

haproxy軟體包下載官網:https://www.haproxy.org//

//安裝依賴包
[root@localhost ~]# yum -y install make gcc pcre-devel bzip2-devel openssl-devel systemd-devel

//創建haproxy用戶
[root@localhost ~]# useradd -r -M -s /sbin/nologin haproxy

//解壓下載好的安裝包
[root@localhost src]# ls
debug  haproxy-2.4.0.tar.gz  kernels
[root@localhost src]# tar xf haproxy-2.4.0.tar.gz -C /usr/src/
[root@localhost src]# ls
debug  haproxy-2.4.0  haproxy-2.4.0.tar.gz  kernels
[root@localhost src]# 

//編譯安裝
[root@localhost src]# cd haproxy-2.4.0/
[root@localhost haproxy-2.4.0]# 
[root@localhost haproxy-2.4.0]# make clean
[root@localhost haproxy-2.4.0]# make -j $(nproc) TARGET=linux-glibc \
> USE_OPENSSL=1 USE_PCRE=1 USE_SYSTEMD=1
[root@localhost haproxy-2.4.0]# make install prefix=/usr/local/haproxy

//配置內核引數
[root@localhost ~]# echo 'net.ipv4.ip_nonlocal_bind = 1' >>  /etc/sysctl.conf
[root@localhost ~]# echo 'net.ipv4.ip_forward = 1' >> /etc/sysctl.conf
[root@localhost ~]# sysctl  -p 
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1
[root@localhost ~]# 

//提供組態檔
[root@localhost ~]# cd /etc/haproxy/
[root@localhost haproxy]# vim haproxy.cfg 
[root@localhost haproxy]# cat haproxy.cfg 
#--------------全域配置----------------
global
    log 127.0.0.1 local0  info
    #log loghost local0 info
    maxconn 20480
#chroot /usr/local/haproxy
    pidfile /var/run/haproxy.pid
    #maxconn 4000
    user haproxy
    group haproxy
    daemon
#---------------------------------------------------------------------
#common defaults that all the 'listen' and 'backend' sections will
#use if not designated in their block
#---------------------------------------------------------------------
defaults
    mode http
    log global
    option dontlognull
    option httpclose
    option httplog
    #option forwardfor
    option redispatch
    balance roundrobin
    timeout connect 10s
    timeout client 10s
    timeout server 10s
    timeout check 10s
    maxconn 60000
    retries 3
#--------------統計頁面配置------------------
listen admin_stats
    bind 0.0.0.0:8189
    stats enable
    mode http
    log global
    stats uri /haproxy_stats
    stats realm Haproxy\ Statistics
    stats auth admin:admin
    #stats hide-version
    stats admin if TRUE
    stats refresh 30s
#---------------web設定-----------------------
listen webcluster
    bind 0.0.0.0:80
    mode http
    #option httpchk GET /index.html
    log global
    maxconn 3000
    balance roundrobin
    server web01 192.168.35.137:80  check inter 2000 fall 5
    server web02 192.168.35.138:80  check inter 2000 fall 5
[root@localhost haproxy]# 

//haproxy.service檔案撰寫
[root@localhost ~]# cat /usr/lib/systemd/system/haproxy.service 
[Unit]
Description=HAProxy Load Balancer
After=syslog.target network.target

[Service]
ExecStartPre=/usr/local/sbin/haproxy -f /etc/haproxy/haproxy.cfg   -c -q
ExecStart=/usr/local/sbin/haproxy -Ws -f /etc/haproxy/haproxy.cfg  -p /var/run/haproxy.pid
ExecReload=/bin/kill -USR2 $MAINPID

[Install]
WantedBy=multi-user.target
[root@localhost ~]#

[root@localhost ~]# systemctl enable --now haproxy.service 
Created symlink /etc/systemd/system/multi-user.target.wants/haproxy.service → /usr/lib/systemd/system/haproxy.service.
[root@localhost ~]# 

[root@localhost ~]# ss -antl
State        Recv-Q       Send-Q             Local Address:Port             Peer Address:Port       
LISTEN       0            128                    127.0.0.1:6010                  0.0.0.0:*          
LISTEN       0            128                      0.0.0.0:8189                  0.0.0.0:*          
LISTEN       0            128                      0.0.0.0:111                   0.0.0.0:*          
LISTEN       0            128                      0.0.0.0:80                    0.0.0.0:*          
LISTEN       0            128                      0.0.0.0:22                    0.0.0.0:*          
LISTEN       0            5                      127.0.0.1:631                   0.0.0.0:*          
LISTEN       0            128                        [::1]:6010                     [::]:*          
LISTEN       0            128                         [::]:111                      [::]:*          
LISTEN       0            128                         [::]:22                       [::]:*          
LISTEN       0            5                          [::1]:631                      [::]:*          
[root@localhost ~]#

//啟用日志
[root@localhost ~]# vim /etc/rsyslog.conf 
 65 local0.*        /var/log/haproxy.log   //添加這一行
[root@localhost ~]# systemctl restart rsyslog.service 

//在web主機上安裝httpd服務
[root@web01 ~]# yum -y install httpd
[root@web01 ~]# echo "web01" > /var/www/html/index.html
[root@web01 ~]# systemctl restart httpd.service 

[root@web02 ~]# yum -y install httpd
[root@web02 ~]#  echo "web02" > /var/www/html/index.html
[root@web02 ~]# systemctl restart httpd.service

3. haproxy配置負載均衡（https）

//證書生成
[root@web01 ~]# yum -y install openssl
[root@web01 ~]# mkdir ~/keys
[root@web01 ~]# cd keys/
[root@web01 keys]# openssl genrsa -out passport.com.key 2048
Generating RSA private key, 2048 bit long modulus (2 primes)
.............................+++++
......+++++
e is 65537 (0x010001)
[root@web01 keys]# openssl req -new -key passport.com.key -out passport.com.csr
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
-----
Country Name (2 letter code) [XX]:CN
State or Province Name (full name) []:HuBei
Locality Name (eg, city) [Default City]:WuHan
Organization Name (eg, company) [Default Company Ltd]:test
Organizational Unit Name (eg, section) []:passport
Common Name (eg, your name or your server's hostname) []:web01.com
Email Address []:passport@qq.com

Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:1
string is too short, it needs to be at least 4 bytes long
A challenge password []:1@2.com
An optional company name []:
[root@web01 keys]# openssl x509 -req -days 3650 -in passport.com.csr -signkey passport.com.key -out passport.com.crt
Signature ok
subject=C = CN, ST = HuBei, L = WuHan, O = test, OU = passport, CN = web01.com, emailAddress = passport@qq.com
Getting Private key
[root@web01 keys]# ls
passport.com.crt  passport.com.csr  passport.com.key

//利用scp命令將證書發送到另外一臺主機上
[root@web01 keys]# scp passport.com.crt passport.com.key 192.168.35.137:/root/
The authenticity of host '192.168.35.137 (192.168.35.137)' can't be established.
ECDSA key fingerprint is SHA256:ECsvugl1DCHfuejtUk08a5piC1AmP1akOaWPFqszmFE.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added '192.168.35.137' (ECDSA) to the list of known hosts.
root@192.168.35.137's password: 
passport.com.crt                                                  100% 1294   899.0KB/s   00:00    
passport.com.key   

//在web兩臺主機上配置https，注意web01需要同樣的步驟
[root@web02 ~]# mkdir  /etc/httpd/ssl
[root@web02 ~]# mv passport.com.* /etc/httpd/ssl/
[root@web02 ~]# cd /etc/httpd/ssl/
[root@web02 ssl]# ls
passport.com.crt  passport.com.key
[root@web02 ssl]# cd ..
[root@web02 httpd]# ls
conf  conf.d  conf.modules.d  logs  modules  run  ssl  state
[root@web02 httpd]# cd conf.d/
[root@web02 conf.d]# ls
autoindex.conf  README  ssl.conf  userdir.conf  welcome.conf
[root@web02 conf.d]# vim ssl.conf 
43 DocumentRoot "/var/www/html"   //取消這兩行注釋
44 ServerName www.example.com:443
85 SSLCertificateFile /etc/httpd/ssl/passport.com.crt   //修改路徑
93 SSLCertificateKeyFile /etc/httpd/ssl/passport.com.key   //修改路徑

//修改組態檔haproxy.cfg
[root@localhost haproxy]# cat haproxy.cfg 
#--------------全域配置----------------
global
    log 127.0.0.1 local0  info
    #log loghost local0 info
    maxconn 20480
#chroot /usr/local/haproxy
    pidfile /var/run/haproxy.pid
    #maxconn 4000
    user haproxy
    group haproxy
    daemon
#---------------------------------------------------------------------
#common defaults that all the 'listen' and 'backend' sections will
#use if not designated in their block
#---------------------------------------------------------------------
defaults
    mode tcp   //修改為tcp
    log global
    option dontlognull
    option httpclose
    option httplog
    #option forwardfor
    option redispatch
    balance roundrobin
    timeout connect 10s
    timeout client 10s
    timeout server 10s
    timeout check 10s
    maxconn 60000
    retries 3
#--------------統計頁面配置------------------
listen admin_stats
    bind 0.0.0.0:8189
    stats enable
    mode http
    log global
    stats uri /haproxy_stats
    stats realm Haproxy\ Statistics
    stats auth admin:admin
    #stats hide-version
    stats admin if TRUE
    stats refresh 30s
#---------------web設定-----------------------
listen webcluster
    bind 0.0.0.0:443   //修改埠為443
    mode tcp   //修改為tcp
    #option httpchk GET /index.html
    log global
    maxconn 3000
    balance roundrobin
    server web01 192.168.35.137:443  check inter 2000 fall 5   //修改埠為443
    server web02 192.168.35.138:443  check inter 2000 fall 5   //修改埠為443
[root@localhost haproxy]# 
[root@localhost haproxy]# systemctl restart haproxy.service

還可以登陸到后臺查看web主機的資訊和運行情況