Rails deployment using capistrano

I am trying to deploy my rails app from local windows machine to a vps .
I use
-Ruby 1.9.3
-Rails 3.2.1
-Capistrano 3.2.1
My server os is Ubuntu 14.04.1 LTS
I am able to run “cap production deploy:setup_config” successfully, when
I try to “cap deploy production” I get - “LoadError: cannot load such
file – nokogiri”.

logs

SSHKit::runner::ExecuteError: Exception while executing on host
xxx.xxx.xxx.xxx: rake exit status: 1
rake stdout: Nothing written
rake stderr: DEPRECATION WARNING: Support for Rails < 3.2.13 will be
dropped from Formtastic 3.0. (called from require a
t
/home/xtech/.rvm/gems/ruby-1.9.3-p547@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:76)
rake aborted!
LoadError: cannot load such file – nokogiri
/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in
requ ire' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in bloc
k in require’
/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:236:in
load _dependency' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in requ
ire’
/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/fog-1.23.0/lib/fog/xml.rb:1:in
<top (required)>' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in requ
ire’
/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in
bloc k in require' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:236:in load
_dependency’
/home/username/apps/app_name/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in
requ ire' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/fog-1.23.0/lib/fog.rb:11:in <top (required)>’
/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in
requ ire' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in bloc
k in require’
/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:236:in
load _dependency' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in requ
ire’
/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/carrierwave-0.10.0/lib/carrierwave/storage/fog.rb:3:in
<top (requi red)>' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in requ
ire’
/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in
bloc k in require' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:236:in load
_dependency’
/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in
requ ire' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/carrierwave-0.10.0/lib/carrierwave/storage.rb:9:in <top (required)


/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in
requ ire' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in bloc
k in require’
/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:236:in
load _dependency' /home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/activesupport-3.2.1/lib/active_support/dependencies.rb:251:in requ
ire’
/home/username/apps/app_name/shared/bundle/ruby/1.9.1/gems/carrierwave-0.10.0/lib/carrierwave.rb:78:in
<top (required)>' /home/username/.rvm/gems/ruby-1.9.3-p547@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:76:in require’
/home/username/.rvm/gems/ruby-1.9.3-p547@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:76:in
block (2 levels) in requir e' /home/username/.rvm/gems/ruby-1.9.3-p547@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:72:in each’
/home/username/.rvm/gems/ruby-1.9.3-p547@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:72:in
block in require' /home/username/.rvm/gems/ruby-1.9.3-p547@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:61:in each’
/home/username/.rvm/gems/ruby-1.9.3-p547@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:61:in
require' /home/username/.rvm/gems/ruby-1.9.3-p547@global/gems/bundler-1.6.2/lib/bundler.rb:132:in require’
/home/username/apps/app_name/releases/20140920131442/config/application.rb:7:in
<top (required)>' /home/username/apps/app_name/releases/20140920131442/Rakefile:5:in require’
/home/username/apps/app_name/releases/20140920131442/Rakefile:5:in `<top
(required)>’
(See full trace by running task with --trace)

I have referred the following links: