ruby-on-rails-Nginx,Unicorn和Rails = 502错误网关

我正在尝试设置Nginx,Unicorn和Rails应用程序以一起工作.
Nginx和Nnicorn正在运行,我使用ps命令进行了检查.

但是当我尝试访问我的页面时,我却遇到了502 Bad Gateway

Nginx错误日志包含以下行：

2015/03/18 19:53:26 [error] 14319#0: *1 connect() to
unix:/var/sockets/unicorn.mypage.sock failed (11: Resource temporarily
unavailable) while connecting to upstream

可能是什么问题？

我的/etc/nginx/conf.d/default.conf

upstream app {
    server unix:/var/sockets/unicorn.mypage.sock fail_timeout=0;
}

server {

    listen 80;
    server_name mypage.com;

    # Application root,as defined previously
    root /home/rails/mypage/public;

    location ^~ /assets/ {
      gzip_static on;
      expires max;
      add_header Cache-Control public;
    }

    try_files $uri/index.html $uri @app;

    location @app {
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;
        proxy_redirect off;
        proxy_pass http://app;
    }

    error_page 500 502 503 504 /500.html;
    client_max_body_size 4G;
    keepalive_timeout 10;
}

/home/rails/mypage/config/unicorn.rb

working_directory "/home/rails/mypage"

pid "/home/rails/mypage/pids/unicorn.pid"

stderr_path "/home/rails/mypage/log/unicorn.log"
stdout_path "/home/rails/mypage/log/unicorn.log"

listen "/var/sockets/unicorn.mypage.sock",backlog: 1024

worker_processes 2

timeout 30