cap log

    triggering load callbacks
  * executing `staging'
    triggering start callbacks for `deploy'
  * executing `multistage:ensure'
  * executing `deploy'
  * executing `deploy:update'
 ** transaction: start
  * executing `deploy:update_code'
  * executing "ls -x /var/www/avalon/releases"
    servers: ["lancelot.dlib.indiana.edu"]
Password: 
    [lancelot.dlib.indiana.edu] executing command
    command finished in 568ms
  * executing "cd /var/www/avalon/releases/20130408165759"
    servers: ["lancelot.dlib.indiana.edu"]
    [lancelot.dlib.indiana.edu] executing command
    command finished in 432ms
  * executing "sudo -p 'sudo password: ' -u avalon git checkout Gemfile.lock"
    servers: ["lancelot.dlib.indiana.edu"]
    [lancelot.dlib.indiana.edu] executing command
 ** [out :: lancelot.dlib.indiana.edu] 
 ** [out :: lancelot.dlib.indiana.edu] fatal: Cannot change to '/home/vov/..': Permission denied
    command finished in 449ms
failed: "rvm_path=$HOME/.rvm/ $HOME/.rvm/bin/rvm-shell 'ruby-1.9.3@avalon' -c 'sudo -p '\\''sudo password: '\\'' -u avalon git checkout Gemfile.lock'" on lancelot.dlib.indiana.edu

deploy.rb

set :default_stage, "staging"
require 'capistrano/ext/multistage'
require 'rvm/capistrano'
require 'whenever/capistrano'

set :application, "avalon"
set :repository,  "git://github.com/avalonmediasystem/avalon.git"

set :scm, :git
# Or: `accurev`, `bzr`, `cvs`, `darcs`, `git`, `mercurial`, `perforce`, `subversion` or `none`

set :deploy_to, "/var/www/avalon/"
set :user, "vov"
set :use_sudo, true

#set :rvm_type, :root
set :rvm_ruby_string, 'ruby-1.9.3@avalon'                     # Or:
#set :rvm_ruby_string, ENV['GEM_HOME'].gsub(/.*\//,"") # Read from local system

task :uname do
  run "uname -a"
end

staging.rb

sudo "git checkout Gemfile.lock", as: "avalon"