Postgres won't connect to server in Ruby on Rails app using c9.io -

a few days ago, able install postgresql , create/migrate databases on sqlite (in preparation deploying rails 4 app)...or thought.

i restarted server, when try access app, error:

pg::connectionbad not connect server: connection refused  server running locally , accepting connections on unix domain socket  "/var/run/postgresql/.s.pgsql.5432"? 

i've seen several similar answered questions on so, involve macs. since i'm using cloud 9 ide instead, thought there might differences (for instance, mentions of localhost not relevant, because that's not how access app on c9.io.)

according answers on other questions, tried in terminal:

sudo ps auxw | grep post 

which gave me:

ubuntu    2527  0.0  0.0  10552   888 pts/5    s+   15:21   0:00 grep --color=auto post 

then tried:

sudo find / -name .s.pgsql.5432 -ls 

and got:

5286    0 lrwxrwxrwx   1 root     root           26 may 11 15:13 /var/pgsql_socket/.s.pgsql.5432 -> /private/tmp/.s.pgsql.5432 5183    0 srwxrwxrwx   1 postgres postgres        0 may 10 22:18 /run/postgresql/.s.pgsql.5432  yamilethmedina@wheels_registration:~/workspace (master|merging) $ psql psql: not connect server: connection refused     server running locally , accepting     connections on unix domain socket "/var/run/postgresql/.s.pgsql.5432"? 

here full trace of server:

started "/" 12.43.117.2 @ 2015-05-11 16:35:48 +0000  pg::connectionbad (could not connect server: connection refused     server running locally , accepting     connections on unix domain socket "/var/run/postgresql/.s.pgsql.5432"? ): activerecord (4.1.6) lib/active_record/connection_adapters/postgresql_adapter.rb:888:in `initialize' activerecord (4.1.6) lib/active_record/connection_adapters/postgresql_adapter.rb:888:in `new' activerecord (4.1.6) lib/active_record/connection_adapters/postgresql_adapter.rb:888:in `connect' activerecord (4.1.6) lib/active_record/connection_adapters/postgresql_adapter.rb:568:in `initialize' activerecord (4.1.6) lib/active_record/connection_adapters/postgresql_adapter.rb:41:in `new' activerecord (4.1.6) lib/active_record/connection_adapters/postgresql_adapter.rb:41:in  `postgresql_connection' activerecord (4.1.6) lib/active_record/connection_adapters/abstract/connection_pool.rb:435:in `new_connection' activerecord (4.1.6) lib/active_record/connection_adapters/abstract/connection_pool.rb:445:in `checkout_new_connection' activerecord (4.1.6) lib/active_record/connection_adapters/abstract/connection_pool.rb:416:in `acquire_connection' activerecord (4.1.6) lib/active_record/connection_adapters/abstract/connection_pool.rb:351:in `block in checkout' /usr/local/rvm/rubies/ruby-2.1.5/lib/ruby/2.1.0/monitor.rb:211:in `mon_synchronize' activerecord (4.1.6) lib/active_record/connection_adapters/abstract/connection_pool.rb:350:in `checkout' activerecord (4.1.6)  lib/active_record/connection_adapters/abstract/connection_pool.rb:265:in `block in connection' /usr/local/rvm/rubies/ruby-2.1.5/lib/ruby/2.1.0/monitor.rb:211:in `mon_synchronize' activerecord (4.1.6) lib/active_record/connection_adapters/abstract/connection_pool.rb:264:in `connection' activerecord (4.1.6) lib/active_record/connection_adapters/abstract/connection_pool.rb:541:in `retrieve_connection' activerecord (4.1.6) lib/active_record/connection_handling.rb:113:in `retrieve_connection' activerecord (4.1.6) lib/active_record/connection_handling.rb:87:in `connection' activerecord (4.1.6) lib/active_record/migration.rb:388:in `check_pending!' activerecord (4.1.6) lib/active_record/migration.rb:377:in `call' actionpack (4.1.6) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call' activesupport (4.1.6) lib/active_support/callbacks.rb:82:in `run_callbacks' actionpack (4.1.6) lib/action_dispatch/middleware/callbacks.rb:27:in `call' actionpack (4.1.6) lib/action_dispatch/middleware/reloader.rb:73:in `call' actionpack (4.1.6) lib/action_dispatch/middleware/remote_ip.rb:76:in `call' actionpack (4.1.6) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call' actionpack (4.1.6) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call' railties (4.1.6) lib/rails/rack/logger.rb:38:in `call_app' railties (4.1.6) lib/rails/rack/logger.rb:20:in `block in call' activesupport (4.1.6) lib/active_support/tagged_logging.rb:68:in `block in tagged' activesupport (4.1.6) lib/active_support/tagged_logging.rb:26:in `tagged' activesupport (4.1.6) lib/active_support/tagged_logging.rb:68:in `tagged' railties (4.1.6) lib/rails/rack/logger.rb:20:in `call' actionpack (4.1.6) lib/action_dispatch/middleware/request_id.rb:21:in `call' rack (1.5.2) lib/rack/methodoverride.rb:21:in `call' rack (1.5.2) lib/rack/runtime.rb:17:in `call' activesupport (4.1.6)   lib/active_support/cache/strategy/local_cache_middleware.rb:26:in `call' rack (1.5.2) lib/rack/lock.rb:17:in `call' actionpack (4.1.6) lib/action_dispatch/middleware/static.rb:64:in `call' rack (1.5.2) lib/rack/sendfile.rb:112:in `call' railties (4.1.6) lib/rails/engine.rb:514:in `call' railties (4.1.6) lib/rails/application.rb:144:in `call' rack (1.5.2) lib/rack/lock.rb:17:in `call' rack (1.5.2) lib/rack/content_length.rb:14:in `call' rack (1.5.2) lib/rack/handler/webrick.rb:60:in `service' /usr/local/rvm/rubies/ruby-2.1.5/lib/ruby/2.1.0/webrick/httpserver.rb:138:in `service' /usr/local/rvm/rubies/ruby-2.1.5/lib/ruby/2.1.0/webrick/httpserver.rb:94:in `run' /usr/local/rvm/rubies/ruby-2.1.5/lib/ruby/2.1.0/webrick/server.rb:295:in `block in start_thread'   rendered /usr/local/rvm/gems/ruby-2.1.5@rails4/gems/actionpack-4.1.6/lib/action_dispatch/middleware/templates/rescues/_source.erb (1.1ms) rendered /usr/local/rvm/gems/ruby-2.1.5@rails4/gems/actionpack-4.1.6/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb (3.8ms) rendered /usr/local/rvm/gems/ruby-2.1.5@rails4/gems/actionpack-4.1.6/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb (2.9ms) rendered /usr/local/rvm/gems/ruby-2.1.5@rails4/gems/actionpack-4.1.6/lib/action_dispatch/middleware/templates/rescues/diagnostics.erb within rescues/layout (45.7ms) 

my entire github repo in case: https://github.com/yamilethmedina/wheels_registration.git

it doesn't postgresql running. perhaps not set auto start. 1 reason can if postgresql wasn't cleanly shutdown on last run, , leaves pid file laying around.

try

  sudo service postgresql start  

and see if comes back, , make sure shut vm down (so stop scripts can run) opposed powering off.