nginx同一个端口不同域名访问不同路径

注：转自nginx实现不同域名映射到一个端口转发到不同路径
在一个服务器中，两个不同的域名a.site.com和b.site.com访问80端口，转发到不同的地址。若通过ip访问，默认转发至pic.mydomain.com对应的地址

server {
        listen       80 default_server;
        listen       [::]:80 default_server;
        server_name  pic.mydomain.com;
        root         /usr/share/nginx/html;

        # Load configuration files for the default server block.
        include /etc/nginx/default.d/*.conf;

        location / {

            add_header backendIP $upstream_addr;
            add_header backendCode $upstream_status;
            proxy_pass http://mysvr;
            proxy_set_header Host myoss.oss-cn-shenzhen-internal.aliyuncs.com;
        }

        error_page 404 /404.html;
            location = /40x.html {
        }

        error_page 500 502 503 504 /50x.html;
            location = /50x.html {
        }
    }

    ## one port,mutil domain,access difference route
    server {
        listen 80;
        server_name www.mydomain.com;
        location / {
            proxy_pass http://localtomcatserver/mywebsite;
        }

        error_page 404 /404.html;
            location = /40x.html {
        }

        error_page 500 502 503 504 /50x.html;
            location /50x.html {
        }
    }

    upstream mysvr {
        server oss-cn-shenzhen-internal.aliyuncs.com;
    }

    upstream localtomcatserver {
        server localhost:8080;
    }

这里的每个地址都是反向代理，如果需要，可以改为不同的root即可