Rieles, pasajero y Memcached: no se puede encontrar el servidor durante la inicialización

Question

Espero que alguien me pueda ayudar con un problema que estoy seguro es un error de usuario.

Los detalles de configuración a continuación funcionan en todos mis otros entornos, incluidos integración, desarrollo y qa. Sin embargo, los servidores de producción dan el siguiente error:

<ActionController::Session::MemCacheStore:0x2b45f6acb248> unable to find server during initialization. 

Cuando el telnet de I a la caja de memcached desde el servidor que tiene el problema y correr 'alta', me sale:

STAT pid 16136 
STAT uptime 7398638 
STAT time 1275059978  
STAT version 1.2.8  
STAT pointer_size 64 
STAT rusage_user 7.085922 
STAT rusage_system 13.275981 
STAT curr_items 10878 
STAT total_items 11441 
STAT bytes 2020180 
STAT curr_connections 5 
STAT total_connections 306 
STAT connection_structures 11 
STAT cmd_flush 0 
STAT cmd_get 457326 
STAT cmd_set 11441 
STAT get_hits 412184 
STAT get_misses 45142 
STAT evictions 0 
STAT bytes_read 22600329 
STAT bytes_written 53036649 
STAT limit_maxbytes 30064771072 
STAT threads 5 
STAT accepting_conns 1 
STAT listen_disabled_num 0 

A continuación se presentan la configuración detalles y stacktrace.

config/environment.rb (las partes importantes):

config.action_controller.session_store = :mem_cache_store 
config.gem "memcache-client", :lib => 'memcache' 

config/ambientes/production.rb:

config.cache_store = :mem_cache_store 

require 'memcache' 

# Caching 
# Memcached configuration 
memcache_options = { 
    :c_threshold => 100_000, 
    :compression => true, 
    :debug => false, 
    :namespace => 'gucci', 
    :readonly => false, 
    :urlencode => false, 
    :multithread => true 
} 

CACHE = MemCache.new memcache_options 
CACHE.servers = ['10.x.x.x:11211'] 

StackTrace:

/var/www/oro/production/releases/20100528130253/vendor/rails/actionpack/lib/action_controller/session/mem_cache_store.rb 20  in `initialize' 
1 /var/www/oro/production/releases/20100528130253/vendor/rails/actionpack/lib/action_controller/middleware_stack.rb 72 in `new' 
2 /var/www/oro/production/releases/20100528130253/vendor/rails/actionpack/lib/action_controller/middleware_stack.rb 72 in `build' 
3 /var/www/oro/production/releases/20100528130253/vendor/rails/actionpack/lib/action_controller/middleware_stack.rb 116  in `build' 
4 /var/www/oro/production/releases/20100528130253/vendor/rails/activesupport/lib/active_support/inflector.rb 361  in `inject' 
5 /var/www/oro/production/releases/20100528130253/vendor/rails/actionpack/lib/action_controller/middleware_stack.rb 116  in `each' 
6 /var/www/oro/production/releases/20100528130253/vendor/rails/actionpack/lib/action_controller/middleware_stack.rb 116  in `inject' 
7 /var/www/oro/production/releases/20100528130253/vendor/rails/actionpack/lib/action_controller/middleware_stack.rb 116  in `build' 
8 /var/www/oro/production/releases/20100528130253/vendor/rails/actionpack/lib/action_controller/dispatcher.rb  130  in `build_middleware_stack' 
9 /var/www/oro/production/releases/20100528130253/vendor/rails/actionpack/lib/action_controller/dispatcher.rb  81 in `initialize' 
10 /var/www/oro/production/releases/20100528130253/vendor/rails/actionpack/lib/action_controller/dispatcher.rb  51 in `new' 
11 /var/www/oro/production/releases/20100528130253/vendor/rails/actionpack/lib/action_controller/dispatcher.rb  51 in `run_prepare_callbacks' 
12 /var/www/oro/production/releases/20100528130253/vendor/rails/railties/lib/initializer.rb 631  in `prepare_dispatcher' 
13 /var/www/oro/production/releases/20100528130253/vendor/rails/railties/lib/initializer.rb 185  in `process' 
14 /var/www/oro/production/releases/20100528130253/vendor/rails/railties/lib/initializer.rb 113  in `send' 
15 /var/www/oro/production/releases/20100528130253/vendor/rails/railties/lib/initializer.rb 113  in `run' 
16 /var/www/oro/production/releases/20100528130253/config/environment.rb 29 
17 /usr/local//lib/ruby/site_ruby/1.8/rubygems/custom_require.rb 31 in `gem_original_require' 
18 /usr/local//lib/ruby/site_ruby/1.8/rubygems/custom_require.rb 31 in `require' 
19 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/railz/application_spawner.rb 303  in `preload_application' 
20 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/railz/application_spawner.rb 252  in `initialize_server' 
21 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/utils.rb 255  in `report_app_init_status' 
22 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/railz/application_spawner.rb 237  in `initialize_server' 
23 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/abstract_server.rb  194  in `start_synchronously' 
24 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/abstract_server.rb  163  in `start' 
25 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/railz/application_spawner.rb 213  in `start' 
26 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/spawn_manager.rb 262  in `spawn_rails_application' 
27 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/abstract_server_collection.rb 126  in `lookup_or_add' 
28 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/spawn_manager.rb 256  in `spawn_rails_application' 
29 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/abstract_server_collection.rb 80 in `synchronize' 
30 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/abstract_server_collection.rb 79 in `synchronize' 
31 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/spawn_manager.rb 255  in `spawn_rails_application' 
32 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/spawn_manager.rb 154  in `spawn_application' 
33 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/spawn_manager.rb 287  in `handle_spawn_application' 
34 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/abstract_server.rb  352  in `__send__' 
35 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/abstract_server.rb  352  in `main_loop' 
36 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/lib/phusion_passenger/abstract_server.rb  196  in `start_synchronously' 
37 /usr/local/lib/ruby/gems/1.8/gems/passenger-2.2.10/bin/passenger-spawn-server 61 

Answer 1

Sólo me aseguraba, pero no veo dónde está configurando la configuración de la sesión en su constante CACHE:

config.action_controller.session = { 
    :session_key => '_appname', 
    :secret  => 'secret', 
    :cache  => CACHE, 
    :expires  => 10 
} 

Esto podría funcionar para qa/dev/testing, ya que creo que por defecto los rieles buscan la memoria memcached en localhost. Mientras que en la producción parece tener una dirección IP diferente para el servidor de memcached.

Answer 2

En el StackTrace hay 3 líneas:

/var/www/oro/production/releases/20100528130253/config/environment.rb 29 
/usr/local//lib/ruby/site_ruby/1.8/rubygems/custom_require.rb 31 in `gem_original_require' 
/usr/local//lib/ruby/site_ruby/1.8/rubygems/custom_require.rb 31 in `require' 

Parece ser alguna joya falta, por favor revise la environment.rb en la línea 29

¿trató ?:

sudo gem install memcached 

Se está ejecutando memcached?

sudo /etc/init.d/memcached start 

Answer 3

Tuve algunos problemas similares con la gema de memcached y cambié a dali. El desarrollo en dali parece más activo y es significativamente más rápido. Seguí las instrucciones en la página de github y tuve Dali en funcionamiento en unos diez minutos.

Answer 4

Para mí resultó que mi daemon memcache no escuchó 127.0.0.1 sino a localhost. Después de eliminar la opción -l localhost del archivo init funcionó perfectamente. (El valor predeterminado es escuchar en todos los dispositivos.)