NGNX，Passenger，Rails「連接上游時資源暫時不可用」

Question

Ruby 1.8.7，rails 3.0.1 該應用程序已運行良好超過一年，並且在一週內未更新。然而，所有突然去應用程序返回503錯誤。數據庫連接是另一個的Linode - 它運行良好，我可以手動連接到從有問題的服務器的MySQL數據庫，這就是nginx的訪問日誌中說：

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說一切都在運行良好的結束 - 任何想法都可能指向正確的方向？

Answer 1

OK看起來像有一個亞馬遜中斷歷時了我們的Redis數據庫：

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