Deploying with capistrano and 'Host key verification failed.' promble - ruby-on-rails

Question

I'm trying to setup my Rails app on Linode and I'm at the stage of trying to get Capistrano setup.
I have a git server setup on the same server as where I'm deploying. I have my SSH keys setup (I think) -- at least I can SSH in no problem.
Both 'cap deploy:setup' and 'cap deploy:check' run without error.
But then when I try to run 'cap deploy:migrations' I get the following:
ray#ray-ThinkPad-SL:~/mini-saler$ cap deploy:migrations
* executing `deploy:migrations'
* executing `deploy:update_code'
updating the cached checkout on all servers
executing locally: "git ls-remote git#XX.207.243.215:mini-saler.git master"
command finished in 12446ms
* executing "if [ -d /home/railsu/bianbian.com/shared/cached-copy ]; then cd /home/railsu/bianbian.com/shared/cached-copy && git fetch origin && git fetch --tags origin && git reset --hard 8e8aa8f849a9438851a3767b338ab711d6470299 && git clean -d -x -f; else git clone git#XX.207.243.215:mini-saler.git /home/railsu/bianbian.com/shared/cached-copy && cd /home/railsu/bianbian.com/shared/cached-copy && git checkout -b deploy 8e8aa8f849a9438851a3767b338ab711d6470299; fi"
servers: ["XX.207.243.215"]
[XX.207.243.215] executing command
** [XX.207.243.215 :: out] Cloning into /home/railsu/bianbian.com/shared/cached-copy...
** [XX.207.243.215 :: err] Host key verification failed.
** [XX.207.243.215 :: err] fatal: The remote end hung up unexpectedly
command finished in 2009ms
failed: "rvm_path=$HOME/.rvm/ $HOME/.rvm/bin/rvm-shell '1.9.3' -c 'if [ -d /home/railsu/bianbian.com/shared/cached-copy ]; then cd /home/railsu/bianbian.com/shared/cached-copy && git fetch origin && git fetch --tags origin && git reset --hard 8e8aa8f849a9438851a3767b338ab711d6470299 && git clean -d -x -f; else git clone git#XX.207.243.215:mini-saler.git /home/railsu/bianbian.com/shared/cached-copy && cd /home/railsu/bianbian.com/shared/cached-copy && git checkout -b deploy 8e8aa8f849a9438851a3767b338ab711d6470299; fi'" on XX.207.243.215
deploy.rb
set :user, 'railsu'
set :domain, 'XX.207.243.215'
set :application, 'mini-saler'
# adjust if you are using RVM, remove if you are not
$:.unshift(File.expand_path('./lib', ENV['rvm_path']))
require "rvm/capistrano"
set :rvm_ruby_string, '1.9.3'
set :rvm_type, :user
# file paths
set :repository, "git##{domain}:mini-saler.git"
set :deploy_to, "/home/railsu/bianbian.com"
# distribute your applications across servers (the instructions below put them
# all on the same server, defined above as 'domain', adjust as necessary)
role :app, domain
role :web, domain
role :db, domain, :primary => true
# miscellaneous options
set :deploy_via, :remote_cache
set :scm, 'git'
set :branch, 'master'
set :scm_verbose, true
set :use_sudo, false
set :rails_env, :production
namespace :deploy do
desc "cause Passenger to initiate a restart"
task :restart do
run "touch #{current_path}/tmp/restart.txt"
end
desc "reload the database with seed data"
task :seed do
run "cd #{current_path}; rake db:seed RAILS_ENV=#{rails_env}"
end
end
after "deploy:update_code", :bundle_install
desc "install the necessary prerequisites"
task :bundle_install, :roles => :app do
run "cd #{release_path} && bundle install"
end
I can use ssh to connect my vps.

Answer 1

I don't recall if any git commands are called on cap deploy:setup or cap deploy:check - I don't think there are.
Assuming you're using gitolite, check to make sure that your configuration has your railsu user's public key is in the keydir directory.
Or perhaps agent forwarding is what you want? Deploying with Capistrano can help you there.