Nginx返回504错误

我在我的Ubuntu服务器上从Nginx获得了一个504错误,我正在运行使用Unicorn的Rails。

当我查看Nginx的error.log.1时,我看到:

2014/01/21 18:06:02 [error] 698#0: *2 connect() failed (111: Connection refused) while connecting to upstream...

当我试图在Rails production.log中查看时,服务器返回Killed当我尝试重新启动Unicorn时,我得到master failed to start, check stderr log for details

当我运行df -h我得到:

 Filesystem Size Used Avail Use% Mounted on /dev/vda 20G 4.1G 15G 22% / 

当我运行df -i我得到:

 Filesystem Inodes IUsed IFree IUse% Mounted on /dev/vda 1310720 144242 1166478 12% / 

我试图删除production.log文件并重新启动Nginx和Unicorn。 我现在可以重新启动麒麟,但我仍然得到了504错误。

我也在Nginx error.log中看到这个:

 2014/02/09 05:44:55 [error] 2245#0: *23 upstream timed out (110: Connection timed out) while reading response header from upstream, client: 73.187.444.220, server: _, request: "GET /favicon.ico HTTP/1.1", upstream: "http://127.0.0.1:8080/favicon.ico", host: "foo.com" 

请帮忙!