Ruby on Rails application could not be started

There appears to be a database problem.
  • Your config/database.yml may not be written correctly. Please check it and fix any errors.
  • Your database schema may be out of date or nonexistant. Please run rake db:migrate to ensure that the database schema is up-to-date.
  • The database server may not be running. Please check whether it's running, and start it if it isn't.
Error message:
Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2) (Mysql::Error)
Exception class:
Mysql::Error
Application root:
/home/websd/apps/zg-mephisto/releases/20080207152432
Backtrace:
# File Line Location
0 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb 471 in `real_connect'
1 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb 471 in `connect'
2 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb 165 in `initialize'
3 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb 88 in `new'
4 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb 88 in `mysql_connection'
5 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb 291 in `send'
6 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb 291 in `connection='
7 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb 259 in `retrieve_connection'
8 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb 78 in `connection'
9 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/base.rb 1063 in `table_exists?'
10 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/base.rb 1153 in `inspect'
11 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/core_ext/symbol.rb 11 in `__send__'
12 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/core_ext/symbol.rb 11 in `to_proc'
13 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 426 in `collect'
14 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 426 in `log_call'
15 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 222 in `load_missing_constant'
16 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 469 in `const_missing'
17 /home/websd/apps/zg-mephisto/releases/20080207152432/app/models/comment.rb 5
18 /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb 31 in `gem_original_require'
19 /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb 31 in `require'
20 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 496 in `require'
21 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 342 in `new_constants_in'
22 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 496 in `require'
23 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 104 in `require_or_load'
24 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 248 in `load_missing_constant'
25 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 453 in `const_missing'
26 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 465 in `const_missing'
27 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 260 in `load_missing_constant'
28 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 469 in `const_missing'
29 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/plugins/mephisto_comment_email/lib/comment_email_observer.rb 5
30 /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb 31 in `gem_original_require'
31 /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb 31 in `require'
32 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 496 in `require'
33 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 342 in `new_constants_in'
34 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 496 in `require'
35 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 104 in `require_or_load'
36 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 248 in `load_missing_constant'
37 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 453 in `const_missing'
38 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/dependencies.rb 465 in `const_missing'
39 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/inflector.rb 257 in `constantize'
40 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/../../activesupport/lib/active_support/core_ext/string/inflections.rb 148 in `constantize'
41 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/observer.rb 38 in `instantiate_observers'
42 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/observer.rb 36 in `each'
43 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/activerecord/lib/active_record/observer.rb 36 in `instantiate_observers'
44 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/railties/lib/initializer.rb 216 in `load_observers'
45 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/railties/lib/initializer.rb 108 in `process'
46 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/railties/lib/initializer.rb 49 in `send'
47 /home/websd/apps/zg-mephisto/releases/20080207152432/vendor/rails/railties/lib/initializer.rb 49 in `run'
48 ./config/environment.rb 17
49 /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb 31 in `gem_original_require'
50 /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb 31 in `require'
51 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/railz/application_spawner.rb 252 in `preload_application'
52 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/railz/application_spawner.rb 212 in `initialize_server'
53 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/utils.rb 181 in `report_app_init_status'
54 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/railz/application_spawner.rb 201 in `initialize_server'
55 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/abstract_server.rb 166 in `start_synchronously'
56 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/abstract_server.rb 135 in `start'
57 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/abstract_server.rb 112 in `fork'
58 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/abstract_server.rb 112 in `start'
59 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/railz/application_spawner.rb 177 in `start'
60 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/spawn_manager.rb 218 in `spawn_rails_application'
61 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/spawn_manager.rb 213 in `synchronize'
62 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/spawn_manager.rb 213 in `spawn_rails_application'
63 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/spawn_manager.rb 122 in `spawn_application'
64 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/spawn_manager.rb 247 in `handle_spawn_application'
65 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/abstract_server.rb 317 in `__send__'
66 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/abstract_server.rb 317 in `main_loop'
67 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/lib/passenger/abstract_server.rb 168 in `start_synchronously'
68 /usr/lib/ruby/gems/1.8/gems/passenger-2.0.3/bin/passenger-spawn-server 46