No server available (Dalli::RingError)

If you see error like this:

No server available (Dalli::RingError) /usr/local/rvm/gems/ruby-2.1.2/gems/dalli-2.7.2/lib/dalli/ring.rb:45:in `server_for_key' /usr/local/rvm/gems/ruby-2.1.2/gems/dalli-2.7.2/lib/dalli/client.rb:218:in `alive!' /usr/local/rvm/gems/ruby-2.1.2/gems/dalli-2.7.2/lib/rack/session/dalli.rb:19:in `initialize' /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/session/abstract_store.rb:24:in `initialize' /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/session/mem_cache_store.rb:18:in `initialize' /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/stack.rb:43:in `new' /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/stack.rb:43:in `build' /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/stack.rb:118:in `block in build' /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/stack.rb:118:in `each' /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/stack.rb:118:in `inject' /usr/local/rvm/gems/ruby-2.1.2/gems/actionpack-4.1.5/lib/action_dispatch/middleware/stack.rb:118:in `build' /usr/local/rvm/gems/ruby-2.1.2/gems/railties-4.1.5/lib/rails/engine.rb:498:in `app' /usr/local/rvm/gems/ruby-2.1.2/gems/railties-4.1.5/lib/rails/application/finisher.rb:36:in `block in <module:Finisher>' /usr/local/rvm/gems/ruby-2.1.2/gems/railties-4.1.5/lib/rails/initializable.rb:30:in `instance_exec' /usr/local/rvm/gems/ruby-2.1.2/gems/railties-4.1.5/lib/rails/initializable.rb:30:in `run' /usr/local/rvm/gems/ruby-2.1.2/gems/railties-4.1.5/lib/rails/initializable.rb:55:in `block in run_initializers' /usr/local/rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:226:in `block in tsort_each' /usr/local/rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:348:in `block (2 levels) in each_strongly_connected_component' /usr/local/rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:427:in `each_strongly_connected_component_from' /usr/local/rvm/rubies/ruby-2.1.2/lib/ruby/2.1.0/tsort.rb:347:in `block in each_st   /............

It means there are problems with memcached service which must be running on server.

Make sure service is running:

service memcached status

if it is not, then start it:

service memcached start

GUI should start working by now.

Also, make sure that service is in startup list:

chkconfig memcached on