Redmine

centOS 7
redmine 3.3.3
rake shows me 12.0.0
mysql 5.7.18
ruby 2.3.4p301

i have a fresh system and trying to make redmine work. i did steps from a lot of manuals of redmine.org, but the last manual is RedmineInstall. i'm stuck at the step 6, so when i'm running the command

RAILS_ENV=production bundle exec rake db:migrate

i get the following error

** Invoke db:migrate (first_time)
** Invoke environment (first_time)
** Execute environment
** Invoke db:load_config (first_time)
** Execute db:load_config
** Execute db:migrate
rake aborted!
ActiveRecord::ConnectionNotEstablished: No connection pool for ActiveRecord::Base
/usr/local/lib/ruby/gems/2.3.0/gems/activerecord-4.2.7.1/lib/active_record/connection_adapters/abstract/connection_pool.rb:570:in `retrieve_connection'
/usr/local/lib/ruby/gems/2.3.0/gems/activerecord-4.2.7.1/lib/active_record/connection_handling.rb:113:in `retrieve_connection'
/usr/local/lib/ruby/gems/2.3.0/gems/activerecord-4.2.7.1/lib/active_record/connection_handling.rb:87:in `connection'
/usr/local/lib/ruby/gems/2.3.0/gems/activerecord-4.2.7.1/lib/active_record/migration.rb:916:in `initialize'
/usr/local/lib/ruby/gems/2.3.0/gems/activerecord-4.2.7.1/lib/active_record/migration.rb:823:in `new'
/usr/local/lib/ruby/gems/2.3.0/gems/activerecord-4.2.7.1/lib/active_record/migration.rb:823:in `up'
/usr/local/lib/ruby/gems/2.3.0/gems/activerecord-4.2.7.1/lib/active_record/migration.rb:801:in `migrate'
/usr/local/lib/ruby/gems/2.3.0/gems/activerecord-4.2.7.1/lib/active_record/tasks/database_tasks.rb:137:in `migrate'
/usr/local/lib/ruby/gems/2.3.0/gems/activerecord-4.2.7.1/lib/active_record/railties/databases.rake:44:in `block (2 levels) in <top (required)>'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/task.rb:250:in `block in execute'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/task.rb:250:in `each'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/task.rb:250:in `execute'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/task.rb:194:in `block in invoke_with_call_chain'
/usr/local/lib/ruby/2.3.0/monitor.rb:214:in `mon_synchronize'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/task.rb:187:in `invoke_with_call_chain'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/task.rb:180:in `invoke'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/application.rb:152:in `invoke_task'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/application.rb:108:in `block (2 levels) in top_level'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/application.rb:108:in `each'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/application.rb:108:in `block in top_level'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/application.rb:117:in `run_with_threads'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/application.rb:102:in `top_level'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/application.rb:80:in `block in run'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/application.rb:178:in `standard_exception_handling'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/lib/rake/application.rb:77:in `run'
/usr/local/lib/ruby/gems/2.3.0/gems/rake-12.0.0/exe/rake:27:in `<top (required)>'
/usr/local/bin/rake:23:in `load'
/usr/local/bin/rake:23:in `<top (required)>'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/lib/bundler/cli/exec.rb:74:in `load'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/lib/bundler/cli/exec.rb:74:in `kernel_load'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/lib/bundler/cli/exec.rb:27:in `run'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/lib/bundler/cli.rb:360:in `exec'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/lib/bundler/vendor/thor/lib/thor/command.rb:27:in `run'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/lib/bundler/vendor/thor/lib/thor/invocation.rb:126:in `invoke_command'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/lib/bundler/vendor/thor/lib/thor.rb:369:in `dispatch'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/lib/bundler/cli.rb:20:in `dispatch'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/lib/bundler/vendor/thor/lib/thor/base.rb:444:in `start'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/lib/bundler/cli.rb:10:in `start'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/exe/bundle:35:in `block in <top (required)>'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/lib/bundler/friendly_errors.rb:121:in `with_friendly_errors'
/usr/local/lib/ruby/gems/2.3.0/gems/bundler-1.15.1/exe/bundle:27:in `<top (required)>'
/usr/local/bin/bundle:23:in `load'
/usr/local/bin/bundle:23:in `<main>'
Tasks: TOP => db:migrate

previous steps seems to go without errors.

database.yml

production:
  adapter: mysql2
  database: redmine
  host: localhost
  username: root
  password: "3av-k>2af)mW" #not an actual password, but alike. maybe special symbols shouldn't be here?
  encoding: utf8

development:
  adapter: mysql2
  database: redmine_development
  host: localhost
  username: root
  password: "3av-k>2af)mW" 
  encoding: utf8

environment.rb

# Load the Rails application
require File.expand_path('../application', __FILE__)

# Make sure there's no plugin in vendor/plugin before starting
vendor_plugins_dir = File.join(Rails.root, "vendor", "plugins")
if Dir.glob(File.join(vendor_plugins_dir, "*")).any?
  $stderr.puts "Plugins in vendor/plugins (#{vendor_plugins_dir}) are no longer allowed. " +
    "Please, put your Redmine plugins in the `plugins` directory at the root of your " +
    "Redmine directory (#{File.join(Rails.root, "plugins")})" 
  exit 1
end

# Initialize the Rails application
#Rails.application.initialize!
# The below line is already in the file
#Rails::Initializer.run do |config|
  # A bunch of stuff
#  config.action_controller.relative_url_root = '/redmine'    # add this line here!
#end

ENV['RAILS_ENV'] ||= 'production'
#RAILS_ENV=production bundle exec rake generate_session_store
#RAILS_ENV=production bundle exec rake db:migrate
#Redmine::Utils::relative_url_root = "/redmine" 

Gemfile is default

source 'https://rubygems.org'

if Gem::Version.new(Bundler::VERSION) < Gem::Version.new('1.5.0')
  abort "Redmine requires Bundler 1.5.0 or higher (you're using #{Bundler::VERSION}).\nPlease update with 'gem update bundler'." 
end

gem "rails", "4.2.7.1" 
gem "addressable", "2.4.0" if RUBY_VERSION < "2.0" 
gem "jquery-rails", "~> 3.1.4" 
gem "coderay", "~> 1.1.1" 
gem "builder", ">= 3.0.4" 
gem "request_store", "1.0.5" 
gem "mime-types", (RUBY_VERSION >= "2.0" ? "~> 3.0" : "~> 2.99")
gem "protected_attributes" 
gem "actionpack-action_caching" 
gem "actionpack-xml_parser" 
gem "roadie-rails" 
gem "mimemagic" 

gem "nokogiri", "~> 1.6.8" 
gem "i18n", "~> 0.7.0" 
gem "ffi", "1.9.14", :platforms => :mingw if RUBY_VERSION < "2.0" 

# Request at least rails-html-sanitizer 1.0.3 because of security advisories 
gem "rails-html-sanitizer", ">= 1.0.3" 

# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
gem 'tzinfo-data', platforms: [:mingw, :x64_mingw, :mswin, :jruby]
gem "rbpdf", "~> 1.19.2" 

# Optional gem for LDAP authentication
group :ldap do
  gem "net-ldap", "~> 0.12.0" 
end

# Optional gem for OpenID authentication
group :openid do
  gem "ruby-openid", "~> 2.3.0", :require => "openid" 
  gem "rack-openid" 
end

platforms :mri, :mingw, :x64_mingw do
  # Optional gem for exporting the gantt to a PNG file, not supported with jruby
  group :rmagick do
    gem "rmagick", ">= 2.14.0" 
  end

  # Optional Markdown support, not for JRuby
  group :markdown do
    gem "redcarpet", "~> 3.3.2" 
  end
end

platforms :jruby do
  # jruby-openssl is bundled with JRuby 1.7.0
  gem "jruby-openssl" if Object.const_defined?(:JRUBY_VERSION) && JRUBY_VERSION < '1.7.0'
  gem "activerecord-jdbc-adapter", "~> 1.3.2" 
end

# Include database gems for the adapters found in the database
# configuration file
require 'erb'
require 'yaml'
database_file = File.join(File.dirname(__FILE__), "config/database.yml")
if File.exist?(database_file)
  database_config = YAML::load(ERB.new(IO.read(database_file)).result)
  adapters = database_config.values.map {|c| c['adapter']}.compact.uniq
  if adapters.any?
    adapters.each do |adapter|
      case adapter
      when 'mysql2'
        gem "mysql2", "~> 0.3.11", :platforms => [:mri, :mingw, :x64_mingw]
        gem "activerecord-jdbcmysql-adapter", :platforms => :jruby
      when 'mysql'
        gem "activerecord-jdbcmysql-adapter", :platforms => :jruby
      when /postgresql/
        gem "pg", "~> 0.18.1", :platforms => [:mri, :mingw, :x64_mingw]
        gem "activerecord-jdbcpostgresql-adapter", :platforms => :jruby
      when /sqlite3/
        gem "sqlite3", (RUBY_VERSION < "2.0" && RUBY_PLATFORM =~ /mingw/ ? "1.3.12" : "~>1.3.12"),
                       :platforms => [:mri, :mingw, :x64_mingw]
        gem "jdbc-sqlite3", ">= 3.8.10.1", :platforms => :jruby
        gem "activerecord-jdbcsqlite3-adapter", :platforms => :jruby
      when /sqlserver/
        gem "tiny_tds", "~> 0.6.2", :platforms => [:mri, :mingw, :x64_mingw]
        gem "activerecord-sqlserver-adapter", :platforms => [:mri, :mingw, :x64_mingw]
      else
        warn("Unknown database adapter `#{adapter}` found in config/database.yml, use Gemfile.local to load your own database gems")
      end
    end
  else
    warn("No adapter found in config/database.yml, please configure it first")
  end
else
  warn("Please configure your config/database.yml first")
end

group :development do
  gem "rdoc", "~> 4.3" 
  gem "yard" 
end

group :test do
  gem "minitest" 
  gem "rails-dom-testing" 
  gem "mocha" 
  gem "simplecov", "~> 0.9.1", :require => false
  # For running UI tests
  gem "capybara" 
  gem "selenium-webdriver", "~> 2.53.4" 
end

local_gemfile = File.join(File.dirname(__FILE__), "Gemfile.local")
if File.exists?(local_gemfile)
  eval_gemfile local_gemfile
end

# Load plugins' Gemfiles
Dir.glob File.expand_path("../plugins/*/{Gemfile,PluginGemfile}", __FILE__) do |file|
  eval_gemfile file
end

i tried to uninstall ruby, mysql, gem through yum. and passenger i installed by this article https://www.phusionpassenger.com/library/install/apache/install/oss/el7/