一.实现前的准备
- 以下是实现简单负载均衡的思路，图中的服务器均为虚拟机
- 三台Linux服务器，一台用作Nginx负载均衡（192.168.254.139），另外两台用作Asp.Net Core应用程序承载的服务器（192.168.254.140，192.168.254.141）
- 一台用作于Client的Windows服务器。
二.环境搭建
1.Asp.Net Core程序
就是一个新建的空web应用程序，然后修改了下Startup的中间件，分别部署到2台Ubuntu上。
public class Startup
{
// This method gets called by the runtime. Use this method to add services to the container.
// For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
public void ConfigureServices(IServiceCollection services)
{
} // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
} app.Run(async (context) =>
{
//await context.Response.WriteAsync("this is first web application");
await context.Response.WriteAsync("this is second web application");
});
}
}
2.配置Nginx服务器
-
安装Nginx
- 在Ubuntu终端使用 sudo apt-get install nginx 命令安装Nginx。
- 然后通过 sudo service nginx start 命令启动服务
- 确认浏览器显示Nginx默认登录页。可在http://192.168.254.139/index.nginx-debian.html 访问登录页面。
-
配置Nginx
- 若要将 Nginx 配置为反向代理以将请求转接到 ASP.NET Core 应用，请修改 /etc/nginx/sites-available/default。 sudo vi /etc/nginx/sites-available/default
- 设置proxy_pass后面的参数
- 新增upstream，表示要转接的服务器集合，upstream后面的名字要与proxy_pass后面的参数相对应
- 修改完之后:wq保存，然后 sudo nginx -t 来验证配置文件的语法有没有错误，如果配置文件测试成功，可以通过运行 sudo nginx -s reload 强制 Nginx 选取更改
upstream cluster.com{
server 192.168.254.140 weight=;
server 192.168.254.141 weight=;
}
server {
listen default_server;
# listen [::]: default_server deferred;
# SSL configuration
#
# listen ssl default_server;
# listen [::]: ssl default_server;
#
# Note: You should disable gzip for SSL traffic.
# See: https://bugs.debian.org/773332
#
# Read up on ssl_ciphers to ensure a secure configuration.
# See: https://bugs.debian.org/765782
#
# Self signed certs generated by the ssl-cert package
# Don't use them in a production server!
#
# include snippets/snakeoil.conf;
root /var/www/html;
# Add index.php to the list if you are using PHP
index index.html index.htm index.nginx-debian.html;
server_name _example.com *.example.com;
location / {
proxy_pass http://cluster.com;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection keep-alive;
proxy_set_header Host $host;
proxy_cache_bypass $http_upgrade;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
# First attempt to serve request as file, then
# as directory, then fall back to displaying a .
try_files $uri $uri/ =;
}
# pass PHP scripts to FastCGI server
#
#location ~ \.php$ {
# include snippets/fastcgi-php.conf;
#
# # With php-fpm (or other unix sockets):
# fastcgi_pass unix:/var/run/php/php7.-fpm.sock;
# # With php-cgi (or other tcp sockets):
# fastcgi_pass 127.0.0.1:;
#}
# deny access to .htaccess files, if Apache's document root
# concurs with nginx's one
#
#location ~ /\.ht {
# deny all;
#}
}
2.Client控制台应用程序
class Program
{
static void Main(string[] args)
{
HttpClient httpClient = new HttpClient();
for (int i = ; i < ; i++)
{
string result = httpClient.GetStringAsync("http://192.168.254.139").Result;
Console.WriteLine(result);
}
Console.ReadKey();
}
}
结果如下：
由结果可知，Nginx服务器会根据我们配置Nginx时的权重进行转向，到现在，一个简单的集群已经搭建。