Aplicação Rails: SocketError (getaddrinfo: Nome ou serviço desconhecido):

Question

Eu tenho um aplicativo Rails (Spree) rodando em um servidor Debian / Apache / Passenger. Acabei de ver aleatoriamente o seguinte problema ao tentar acessar a área de administração.

Eu tentei mudar o hostname do meu servidor para 127.0.0.1, atualizei o Passenger, Ruby, todas as gemas, eu também tentei reinstalar o httparty & omniauth sem sorte.

D, [2015-09-10T20:22:10.169700 #4792] DEBUG -- :   Spree::Store Load (0.1ms)  SELECT  'spree_stores'.* FROM 'spree_stores' WHERE 'spree_stores'.'default' = 1  ORDER BY 'spree_stores'.'id' ASC LIMIT 1
I, [2015-09-10T20:22:10.376695 #4792]  INFO -- : Completed 500 Internal Server Error in 211ms
F, [2015-09-10T20:22:10.378766 #4792] FATAL -- : 
SocketError (getaddrinfo: Name or service not known):
  /usr/local/rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/net/http.rb:879:in 'initialize'
  /usr/local/rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/net/http.rb:879:in 'open'
  /usr/local/rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/net/http.rb:879:in 'block in connect'
  /usr/local/rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/timeout.rb:74:in 'timeout'
  /usr/local/rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/net/http.rb:878:in 'connect'
  /usr/local/rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/net/http.rb:863:in 'do_start'
  /usr/local/rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/net/http.rb:852:in 'start'
  /usr/local/rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/net/http.rb:1375:in 'request'
  httparty (0.13.5) lib/httparty/request.rb:101:in 'perform'
  httparty (0.13.5) lib/httparty/request.rb:275:in 'handle_response'
  httparty (0.13.5) lib/httparty/request.rb:115:in 'perform'
  httparty (0.13.5) lib/httparty.rb:522:in 'perform_request'
  httparty (0.13.5) lib/httparty.rb:460:in 'get'
  httparty (0.13.5) lib/httparty.rb:560:in 'get'
  spree_core (3.0.0) app/models/spree/alert.rb:14:in 'current'
  spree_backend (3.0.0) app/controllers/spree/admin/base_controller.rb:38:in 'check_alerts'
  activesupport (4.2.0) lib/active_support/callbacks.rb:427:in 'block in make_lambda'
  activesupport (4.2.0) lib/active_support/callbacks.rb:163:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:163:in 'block in halting'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'block in halting'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'block in halting'
  activesupport (4.2.0) lib/active_support/callbacks.rb:234:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:234:in 'block in halting'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'block in halting'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'block in halting'
  activesupport (4.2.0) lib/active_support/callbacks.rb:234:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:234:in 'block in halting'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'block in halting'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'block in halting'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:169:in 'block in halting'
  activesupport (4.2.0) lib/active_support/callbacks.rb:92:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:92:in '_run_callbacks'
  activesupport (4.2.0) lib/active_support/callbacks.rb:734:in '_run_process_action_callbacks'
  activesupport (4.2.0) lib/active_support/callbacks.rb:81:in 'run_callbacks'
  actionpack (4.2.0) lib/abstract_controller/callbacks.rb:19:in 'process_action'
  actionpack (4.2.0) lib/action_controller/metal/rescue.rb:29:in 'process_action'
  actionpack (4.2.0) lib/action_controller/metal/instrumentation.rb:31:in 'block in process_action'
  activesupport (4.2.0) lib/active_support/notifications.rb:164:in 'block in instrument'
  activesupport (4.2.0) lib/active_support/notifications/instrumenter.rb:20:in 'instrument'
  activesupport (4.2.0) lib/active_support/notifications.rb:164:in 'instrument'
  actionpack (4.2.0) lib/action_controller/metal/instrumentation.rb:30:in 'process_action'
  actionpack (4.2.0) lib/action_controller/metal/params_wrapper.rb:250:in 'process_action'
  activerecord (4.2.0) lib/active_record/railties/controller_runtime.rb:18:in 'process_action'
  actionpack (4.2.0) lib/abstract_controller/base.rb:137:in 'process'
  actionview (4.2.0) lib/action_view/rendering.rb:30:in 'process'
  actionpack (4.2.0) lib/action_controller/metal.rb:195:in 'dispatch'
  actionpack (4.2.0) lib/action_controller/metal/rack_delegation.rb:13:in 'dispatch'
  actionpack (4.2.0) lib/action_controller/metal.rb:236:in 'block in action'
  actionpack (4.2.0) lib/action_dispatch/routing/route_set.rb:73:in 'call'
  actionpack (4.2.0) lib/action_dispatch/routing/route_set.rb:73:in 'dispatch'
  actionpack (4.2.0) lib/action_dispatch/routing/route_set.rb:42:in 'serve'
  actionpack (4.2.0) lib/action_dispatch/journey/router.rb:43:in 'block in serve'
  actionpack (4.2.0) lib/action_dispatch/journey/router.rb:30:in 'each'
  actionpack (4.2.0) lib/action_dispatch/journey/router.rb:30:in 'serve'
  actionpack (4.2.0) lib/action_dispatch/routing/route_set.rb:802:in 'call'
  warden (1.2.3) lib/warden/manager.rb:35:in 'block in call'
  warden (1.2.3) lib/warden/manager.rb:34:in 'catch'
  warden (1.2.3) lib/warden/manager.rb:34:in 'call'
  rack (1.6.4) lib/rack/etag.rb:24:in 'call'
  rack (1.6.4) lib/rack/conditionalget.rb:25:in 'call'
  rack (1.6.4) lib/rack/head.rb:13:in 'call'
  actionpack (4.2.0) lib/action_dispatch/middleware/params_parser.rb:27:in 'call'
  actionpack (4.2.0) lib/action_dispatch/middleware/flash.rb:260:in 'call'
  rack (1.6.4) lib/rack/session/abstract/id.rb:225:in 'context'
  rack (1.6.4) lib/rack/session/abstract/id.rb:220:in 'call'
  actionpack (4.2.0) lib/action_dispatch/middleware/cookies.rb:560:in 'call'
  activerecord (4.2.0) lib/active_record/query_cache.rb:36:in 'call'
  activerecord (4.2.0) lib/active_record/connection_adapters/abstract/connection_pool.rb:647:in 'call'
  actionpack (4.2.0) lib/action_dispatch/middleware/callbacks.rb:29:in 'block in call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:88:in 'call'
  activesupport (4.2.0) lib/active_support/callbacks.rb:88:in '_run_callbacks'
  activesupport (4.2.0) lib/active_support/callbacks.rb:734:in '_run_call_callbacks'
  activesupport (4.2.0) lib/active_support/callbacks.rb:81:in 'run_callbacks'
  actionpack (4.2.0) lib/action_dispatch/middleware/callbacks.rb:27:in 'call'
  actionpack (4.2.0) lib/action_dispatch/middleware/remote_ip.rb:78:in 'call'
  actionpack (4.2.0) lib/action_dispatch/middleware/debug_exceptions.rb:17:in 'call'
  actionpack (4.2.0) lib/action_dispatch/middleware/show_exceptions.rb:30:in 'call'
  railties (4.2.0) lib/rails/rack/logger.rb:38:in 'call_app'
  railties (4.2.0) lib/rails/rack/logger.rb:20:in 'block in call'
  activesupport (4.2.0) lib/active_support/tagged_logging.rb:68:in 'block in tagged'
  activesupport (4.2.0) lib/active_support/tagged_logging.rb:26:in 'tagged'
  activesupport (4.2.0) lib/active_support/tagged_logging.rb:68:in 'tagged'
  railties (4.2.0) lib/rails/rack/logger.rb:20:in 'call'
  actionpack (4.2.0) lib/action_dispatch/middleware/request_id.rb:21:in 'call'
  rack (1.6.4) lib/rack/methodoverride.rb:22:in 'call'
  rack (1.6.4) lib/rack/runtime.rb:18:in 'call'
  activesupport (4.2.0) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in 'call'
  rack (1.6.4) lib/rack/sendfile.rb:113:in 'call'
  railties (4.2.0) lib/rails/engine.rb:518:in 'call'
  railties (4.2.0) lib/rails/application.rb:164:in 'call'
  passenger (5.0.18) lib/phusion_passenger/rack/thread_handler_extension.rb:94:in 'process_request'
  passenger (5.0.18) lib/phusion_passenger/request_handler/thread_handler.rb:149:in 'accept_and_process_next_request'
  passenger (5.0.18) lib/phusion_passenger/request_handler/thread_handler.rb:110:in 'main_loop'
  passenger (5.0.18) lib/phusion_passenger/request_handler.rb:415:in 'block (3 levels) in start_threads'
  passenger (5.0.18) lib/phusion_passenger/utils.rb:112:in 'block in create_thread_and_abort_on_exception'