NGNX，Passenger，Rails“连接上游时资源暂时不可用”

Question

Ruby 1.8.7，rails 3.0.1 该应用程序已运行良好超过一年，并且在一周内未更新。然而，所有突然去应用程序返回503错误。数据库连接是另一个的Linode - 它运行良好，我可以手动连接到从有问题的服务器的MySQL数据库，这就是nginx的访问日志中说：

2012/06/30 03:20:00 [error] 2277#0: *509 connect() to unix:/passenger_helper_server failed (11: Resource temporarily unavailable) while connecting to upstream, client: 192.168.255.12, server: disco, request: "GET/HTTP/1.1", upstream: "passenger:unix:/passenger_helper_server:", host: "*.*.*.*" 
2012/06/30 03:20:12 [error] 2277#0: *511 connect() to unix:/passenger_helper_server failed (11: Resource temporarily unavailable) while connecting to upstream, client: 192.168.255.12, server: disco, request: "GET/HTTP/1.1", upstream: "passenger:unix:/passenger_helper_server:", host: "*.*.*.*" 
2012/06/30 03:20:24 [error] 2277#0: *513 connect() to unix:/passenger_helper_server failed (11: Resource temporarily unavailable) while connecting to upstream, client: 192.168.255.12, server: disco, request: "GET/HTTP/1.1", upstream: "passenger:unix:/passenger_helper_server:", host: "*.*.*.*" 
2012/06/30 03:20:36 [error] 2277#0: *515 connect() to unix:/passenger_helper_server failed (11: Resource temporarily unavailable) while connecting to upstream, client: 192.168.255.12, server: disco, request: "GET/HTTP/1.1", upstream: "passenger:unix:/passenger_helper_server:", host: "*.*.*.*" 
2012/06/30 03:20:48 [error] 2277#0: *517 connect() to unix:/passenger_helper_server failed (11: Resource temporarily unavailable) while connecting to upstream, client: 192.168.255.12, server: disco, request: "GET/HTTP/1.1", upstream: "passenger:unix:/passenger_helper_server:", host: "*.*.*.*" 
2012/06/30 03:21:00 [error] 2277#0: *519 connect() to unix:/passenger_helper_server failed (11: Resource temporarily unavailable) while connecting to upstream, client: 192.168.255.12, server: disco, request: "GET/HTTP/1.1", upstream: "passenger:unix:/passenger_helper_server:", host: "*.*.*.*" 
2012/06/30 03:21:12 [error] 2277#0: *521 connect() to unix:/passenger_helper_server failed (11: Resource temporarily unavailable) while connecting to upstream, client: 192.168.255.12, server: disco, request: "GET/HTTP/1.1", upstream: "passenger:unix:/passenger_helper_server:", host: "*.*.*.*" 
2012/06/30 03:21:24 [error] 2277#0: *523 connect() to unix:/passenger_helper_server failed (11: Resource temporarily unavailable) while connecting to upstream, client: 192.168.255.12, server: disco, request: "GET/HTTP/1.1", upstream: "passenger:unix:/passenger_helper_server:", host: "*.*.*.*" 
2012/06/30 03:21:35 [error] 2277#0: *525 connect() to unix:/passenger_helper_server failed (11: Resource temporarily unavailable) while connecting to upstream, client: 192.168.255.12, server: disco, request: "GET/HTTP/1.1", upstream: "passenger:unix:/passenger_helper_server:", host: "*.*.*.*" 

的Linode说一切都在运行良好的结束 - 任何想法都可能指向正确的方向？

Answer 1

OK看起来像有一个亚马逊中断历时了我们的Redis数据库：

http://www.theregister.co.uk/2012/06/30/amazon_cloud_storm_outage/