Compile:

yum install zlib-devel pcre-devel

user bb;
worker_processes auto;
error_log logs/error.log notice;
pid /var/run/nginx.pid;

events {
  accept_mutex on;
  multi_accept on;
  worker_connections 2048;
  use epoll;
}

http {
  include mime.types;
  default_type application/octet-stream;
  sendfile on;
  keepalive_timeout 30;

  log_format s1 '------> s1';
  log_format s2 '------> s2';

  include conf.d/*.conf;
}

conf.d/

server {
  listen 8081;
  server_name localhost;
  access_log logs/s1.log s1;

  error_page 404 /404.html;

  location /s1/l1 {
    root /home/bb/web;
    index index1.html;
  }

  location /s1/l2 {
    root /home/bb/web1;
    index index2.html;
  }

  location = /404.html {
    root /home/bb/;
    index 404.html;
  }
}

server {
  listen 8082;
  server_name localhost;
  access_log logs/s2.log s2;

  error_page 404 /404.html;

  location /s2/l1 {
    root /home/bb/web2;
    index index1.html;
  }

  location /s2/l2 {
    root /home/bb/web2;
    index index2.html;
  }

  location = /404.html {
    root /home/bb;
    index 404.html;
  }
}