nginx负载均衡配置
Nginx是一个高性能的HTTP和反向代理服务器,可以在4层/7层来实现负载均衡
配置环境：
负载均衡器：server4（172.25.254.4）
real server1:server2(172.25.254.2)
real server2:server3(172.25.254.3)
一、开始配置
server4安装nginx，本次选择nginx-1.14.0.tar.gz版本
[root@server4 ~]# ls
nginx-1.14.0.tar.gz
[root@server4 ~]# tar zxf nginx-1.14.0.tar.gz
[root@server4 ~]# cd nginx-1.14.0
[root@server4 nginx-1.14.0]# ls
auto CHANGES.ru configure html man src
CHANGES conf contrib LICENSE README
为了得到纯净的nginx，我们需要将～/nginx-1.14.0/auto/cc/gcc 中的debug注释掉
如果不注释掉，我们得到的nginx将会大很多
这个为未注释掉的，我们注释掉删除nginx后重新编译
并且隐藏nginx的版本号
[root@server4 nginx-1.14.0]# vim src/core/nginx.h
#define nginx_version 1014000
#define NGINX_VERSION "1.14.0"
#define NGINX_VER "nginx/"
重新编译：
[root@server4 nginx-1.14.0]# ./configure --prefix=/usr/local/nginx --with-http_ssl_module --with-http_stub_status_module --with-threads --with-file-aio ##编译时指定安装路径，并加载相应模块
yum install -y gcc
yum install -y pcre-devel
yum install -y openssl-develyum install -y gcc
安装相应的依赖包
[root@server4 nginx-1.14.0]# make && make install ##编译完成后检测并安装
[root@server4 nginx-1.14.0]# cd /usr/local/nginx/
[root@server4 nginx]# ls
conf html logs sbin
[root@server4 nginx]# ln -s /usr/local/nginx/sbin/nginx /sbin/ ##创建nginx执行脚本软连接
[root@server4 nginx]# du -sh
980K . ##没有debug后的nginx
[root@server4 nginx]# nginx -t ##查看nginx是否有问题
nginx: the configuration file /usr/local/nginx/conf/nginx.conf syntax is ok
nginx: configuration file /usr/local/nginx/conf/nginx.conf test is successful
[root@server4 nginx]# nginx 开启nginx 开启后不能restart，只能-s reload重新加载 开启之前要确保80端口没有被占用
[root@server4 nginx]# curl -I localhost
HTTP/1.1 200 OK
Server: nginx/1.14.0
Date: Wed, 27 Jun 2018 14:53:46 GMT
Content-Type: text/html
Content-Length: 612
Last-Modified: Wed, 27 Jun 2018 14:50:49 GMT
Connection: keep-alive
ETag: "5b33a449-264"
Accept-Ranges: bytes
二、修改配置文件
vim /usr/local/nginx/conf/nginx.conf
1
2 user nginx nginx; ##nginx以nginx用户身份运行，需要建立nginx用户
3 worker_processes 1; ##工作进程，一般设置为auto自动
4
5 #error_log logs/error.log;
6 #error_log logs/error.log notice;
7 #error_log logs/error.log info;
8
9 #pid logs/nginx.pid;
10
11
12 events {
13 use epoll;
14 worker_connections 65535; ##线程，并且在系统中给到比他大的线程
15 }
16
17
18 http {
19 upstream westos{ ##算法
20 server 172.25.254.2:80 weight=2; ##监控server的80端口，weigh为权重，2每访问两次，3访问一词
21 server 172.25.254.3:80;
22 }
23 include mime.types;
121
122
123 server { ##设置虚拟主机
124 listen 80;
125 server_name www.westos.org;
126
127 location / { 调度算法
128 proxy_pass http://westos;
129 }
130 }
131 }
修改系统允许的线程
[root@server4 nginx-1.14.0]# vim /etc/security/limits.conf
50 # End of file
51 nginx - nofile 65536
[root@server4 nginx-1.14.0]# su -
[root@server4 ~]# su - nginx
[nginx@server4 ~]$ ulimit -a
core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 7820
max locked memory (kbytes, -l) 64
max memory size (kbytes, -m) unlimited
open files (-n) 65536
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 10240
cpu time (seconds, -t) unlimited
max user processes (-u) 1024
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited
三、real server配置
开启httpd服务，并保证httpd的端口为80
[root@server2 ~]# /etc/init.d/httpd start
Starting httpd: httpd: Could not reliably determine the server's fully qualified domain name, using 172.25.254.2 for ServerName
[ OK ]
[root@server2 ~]# curl localhost
server2
[root@server2 ~]# netstat -antuple | grep 80
tcp 0 0 :::80 :::* LISTEN 0 8688 1036/httpd
[root@server3 ~]# /etc/init.d/httpd start
Starting httpd: Warning: DocumentRoot [/www/html] does not exist
httpd: Could not reliably determine the server's fully qualified domain name, using 172.25.254.3 for ServerName
[ OK ]
[root@server3 ~]# curl localhost
server3
[root@server3 ~]# netstat -antuple | grep 80
tcp 0 0 :::80 :::* LISTEN 0 8689 1033/httpd
测试：物理机做域名解析后访问：
[root@foundation77 Desktop]# vim /etc/hosts
[root@foundation77 Desktop]# for i in {1..10};do curl www.westos.org;done
server2
server3
server2
server2
server3
server2
server2
server3
server2
server2
四、nginx的其他算法
1、ip_hash模式
[root@server4 ~]# nginx -t
nginx: the configuration file /usr/local/nginx/conf/nginx.conf syntax is ok
nginx: configuration file /usr/local/nginx/conf/nginx.conf test is successful
[root@server4 ~]# vim /usr/local/nginx/conf/nginx.conf
[root@server4 ~]# nginx -s reload
物理机测试：
[root@foundation77 Desktop]# for i in {1..10};do curl www.westos.org;done
server2
server2
server2
server2
server2
server2
server2
server2
server2
server2
2、设置buckup
修改完重新加载nginx
设置完成后修改server4的httpd端口为8080，并打开httpd服务，将server2和server3的httpd服务stop后物理机测试：
[root@foundation77 Desktop]# for i in {1..10};do curl www.westos.org;done
server4
server4
server4
server4
server4
server4
server4
server4
server4
server4
3、cookie
因为nginx1.14不支持此模块，我们用1.10来实现
nginx-1.10.1.tar.gznginx-1.10.1.tar.gz
nginx-sticky-module-ng.tar.gz
[root@server4 ~]# tar zxf nginx-1.10.1.tar.gz
[root@server4 ~]# tar zxf nginx-sticky-module-ng.tar.gz
[root@server4 ~]# cd nginx-1.10.1
[root@server4 nginx-1.10.1]# ./configure --prefix=/opt/nginx --add-module=/root/nginx-sticky-module-ng
[root@server4 nginx-1.10.1]# make && make install
[root@server4 nginx-1.10.1]# cd /opt/nginx/conf/
[root@server4 conf]# cp /usr/local/nginx/conf/nginx.conf .
cp: overwrite `./nginx.conf'? y
[root@server4 conf]# vim nginx.conf
[root@server4 nginx]# sbin/nginx -t
nginx: the configuration file /opt/nginx/conf/nginx.conf syntax is ok
nginx: configuration file /opt/nginx/conf/nginx.conf test is successful
[root@server4 nginx]# sbin/nginx
配置完成后真机apache测试