error

[!]You shold install `padrino-helpers' gem if you want to use kaminari's pagination helpers with Sinatra.
[!]Kaminari::Helpers::SinatraHelper does nothing now...
[deprecated] I18n.enforce_available_locales will default to true in the future. If you really want to skip validation of your locale you can set I18n.enforce_available_locales = false to avoid this message.
/edx/app/forum/.gem/gems/moped-1.5.1/lib/moped/node.rb:503:in `login': The operation: #<Moped::Protocol::Commands::Authenticate (Moped::Errors::AuthenticationFailure)
  @length=176
  @request_id=3
  @response_to=0
  @op_code=2004
  @flags=[]
  @full_collection_name="cs_comments_service.$cmd"
  @skip=0
  @limit=-1
  @selector={:authenticate=>1, :user=>"cs_comments_service", :nonce=>"4c26e39fb41dce47", :key=>"8c4d7012ada468f745f8397cb0680a8b"}
  @fields=nil>
failed with error 18: "auth failed"

See https://github.com/mongodb/mongo/blob/master/docs/errors.md
for details about this error.
	from /edx/app/forum/.gem/gems/moped-1.5.1/lib/moped/node.rb:57:in `block in apply_auth'
	from /edx/app/forum/.gem/gems/moped-1.5.1/lib/moped/node.rb:56:in `each'
	from /edx/app/forum/.gem/gems/moped-1.5.1/lib/moped/node.rb:56:in `apply_auth'
	from /edx/app/forum/.gem/gems/moped-1.5.1/lib/moped/cluster.rb:209:in `block in with_primary'
	from /edx/app/forum/.gem/gems/moped-1.5.1/lib/moped/node.rb:195:in `ensure_primary'
	from /edx/app/forum/.gem/gems/moped-1.5.1/lib/moped/cluster.rb:208:in `with_primary'
	from /edx/app/forum/.gem/gems/newrelic_rpm-3.11.2.286/lib/new_relic/agent/method_tracer.rb:343:in `block in with_primary_with_trace_Custom_Moped_Cluster_with_primary'
	from /edx/app/forum/.gem/gems/newrelic_rpm-3.11.2.286/lib/new_relic/agent/method_tracer_helpers.rb:82:in `trace_execution_scoped'
	from /edx/app/forum/.gem/gems/newrelic_rpm-3.11.2.286/lib/new_relic/agent/method_tracer.rb:341:in `with_primary_with_trace_Custom_Moped_Cluster_with_primary'
	from /edx/app/forum/.gem/gems/moped-1.5.1/lib/moped/session/context.rb:108:in `with_node'
	from /edx/app/forum/.gem/gems/moped-1.5.1/lib/moped/cursor.rb:137:in `load_docs'
	from /edx/app/forum/.gem/gems/moped-1.5.1/lib/moped/cursor.rb:25:in `each'
	from /edx/app/forum/cs_comments_service/app.rb:173:in `each'
	from /edx/app/forum/cs_comments_service/app.rb:173:in `map'
	from /edx/app/forum/cs_comments_service/app.rb:173:in `<top (required)>'
	from /edx/app/forum/.rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
	from /edx/app/forum/.rbenv/versions/1.9.3-p448/lib/ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
	from config.ru:6:in `block in <main>'
	from /edx/app/forum/.gem/gems/rack-1.4.1/lib/rack/builder.rb:51:in `instance_eval'
	from /edx/app/forum/.gem/gems/rack-1.4.1/lib/rack/builder.rb:51:in `initialize'
	from config.ru:1:in `new'
	from config.ru:1:in `<main>'
	from /edx/app/forum/.gem/gems/unicorn-4.3.1/lib/unicorn.rb:44:in `eval'
	from /edx/app/forum/.gem/gems/unicorn-4.3.1/lib/unicorn.rb:44:in `block in builder'
	from /edx/app/forum/.gem/gems/unicorn-4.3.1/lib/unicorn/http_server.rb:696:in `call'
	from /edx/app/forum/.gem/gems/unicorn-4.3.1/lib/unicorn/http_server.rb:696:in `build_app!'
	from /edx/app/forum/.gem/gems/unicorn-4.3.1/lib/unicorn/http_server.rb:136:in `start'
	from /edx/app/forum/.gem/gems/unicorn-4.3.1/bin/unicorn:121:in `<top (required)>'
	from /edx/app/forum/.gem/bin/unicorn:23:in `load'
	from /edx/app/forum/.gem/bin/unicorn:23:in `<main>'
I, [2015-09-01T19:47:52.864162 #22683]  INFO -- : unlinking existing socket=/edx/var/forum/forum.sock
I, [2015-09-01T19:47:52.864952 #22683]  INFO -- : listening on addr=/edx/var/forum/forum.sock fd=5
I, [2015-09-01T19:47:52.865585 #22683]  INFO -- : Refreshing Gem list