发现 Unicorn 并没有打开指定端口 配置

nginx
  upstream app_server {
    # fail_timeout=0 means we always retry an upstream even if it failed
    # to return a good HTTP response (in case the Unicorn master nukes a
    # single worker for timing out).

    # for UNIX domain socket setups:
    #server unix:/path/to/.unicorn.sock fail_timeout=0;    

    # for TCP setups, point these to your backend servers
    # server 192.168.0.7:8080 fail_timeout=0;
    # server 192.168.0.8:8080 fail_timeout=0;    
    server 192.168.1.4:8080 fail_timeout=0;
  }
unicorn
#listen "/tmp/#{application}.sock", :backlog => 256
listen "127.0.0.1:8080"

这导致了 nginx 没法访问 unicorn