配置nginx通过不同path反代至不同后端tomcat（即访问www.a.com/a/反代至tomcat1，访问www.a.com/b/反代至tomcat2）

tomcat1 http://10.0.0.152
tomcat2 http://10.0.0.162

修改nginx.conf
 server {
        listen       80;
        server_name  www.tan.com;

        location ~/a/ {
            proxy_pass http://10.0.0.152:8080;
        }
        location ~/b/{
            proxy_pass http://10.0.0.162:8080;
 }
    }