/home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:80:in `rescue in block (2 levels) in require': There was an error while trying to load the gem 'mysql2'. (Bundler::GemRequireError)
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:76:in `block (2 levels) in require'
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:72:in `each'
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:72:in `block in require'
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:61:in `each'
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:61:in `require'
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/bundler-1.11.2/lib/bundler.rb:99:in `require'
from /home/hien/rails_projects/childfoot/peco_blog/config/application.rb:7:in `<top (required)>'
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/railties-4.2.4/lib/rails/commands/commands_tasks.rb:78:in `require'
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/railties-4.2.4/lib/rails/commands/commands_tasks.rb:78:in `block in server'
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/railties-4.2.4/lib/rails/commands/commands_tasks.rb:75:in `tap'
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/railties-4.2.4/lib/rails/commands/commands_tasks.rb:75:in `server'
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/railties-4.2.4/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
from /home/hien/.rbenv/versions/2.2.3/lib/ruby/gems/2.2.0/gems/railties-4.2.4/lib/rails/commands.rb:17:in `<top (required)>'
from bin/rails:4:in `require'
from bin/rails:4:in `<main>'
fix:
bundle install --without postgres development test --deployment