Capistrano deploy fails when upgrade ruby version in rbenv -

Capistrano deploy fails when upgrade ruby version in rbenv -

when run cap production deploy in rails project directory, error this:

info[6be9dff4] running rbenv_root=/usr/local/rbenv rbenv_version=2.1.1 /usr/local/rbenv/bin/rbenv exec bundle install --binstubs /var/www/example.com/shared/bin --path /var/www/example.com/shared/bundle --without development test --deployment --quiet on example.com debug[6be9dff4] command: cd /var/www/example.com/releases/20140624143014 && ( rbenv_root=/usr/local/rbenv rbenv_version=2.1.1 rbenv_root=/usr/local/rbenv rbenv_version=2.1.1 /usr/local/rbenv/bin/rbenv exec bundle install --binstubs /var/www/example.com/shared/bin --path /var/www/example.com/shared/bundle --without development test --deployment --quiet ) debug[6be9dff4] errno::eacces: permission denied @ rb_sysopen - /var/www/example.com/shared/bundle/ruby/2.1.0/cache/rake-10.3.2.gem debug[6be9dff4] error occurred while installing rake (10.3.2), , bundler cannot continue. debug[6be9dff4] create sure `gem install rake -v '10.3.2'` succeeds before bundling.

so login server , alter user deploy user, run command this:

$ su - deployer password: deployer@server ~$ cd /var/www/example.com/releases/20140624143014 && ( rbenv_root=/usr/local/rbenv rbenv_version=2.1.1 rbenv_root=/usr/local/rbenv rbenv_version=2.1.1 /usr/local/rbenv/bin/rbenv exec bundle install --binstubs /var/www/example.com/shared/bin --path /var/www/example.com/shared/bundle --without development test --deployment --quiet ) errno::eacces: permission denied @ rb_sysopen - /var/www/example.com/shared/bundle/ruby/2.1.0/cache/rake-10.3.2.gem error occurred while installing rake (10.3.2), , bundler cannot continue. create sure `gem install rake -v '10.3.2'` succeeds before bundling.

rbenv , ruby installed this:

$ rbenv versions scheme 2.0.0-p451 * 2.1.1 (set /usr/local/rbenv/version)

i'm tring deploy linuxmint16 centos 6.5 capistrano 3 , prior deploy successful when used 2.0.0-p451.

how , should check find out causes error?

ruby-on-rails ruby