uname.rb

KEY_FILE = '/path/to/aws.pem'

server 'ec2-54-248-135-100.ap-northeast-1.compute.amazonaws.com', :srv1
server 'ec2-54-248-26-71.ap-northeast-1.compute.amazonaws.com', :srv2
server 'ec2-46-51-239-7.ap-northeast-1.compute.amazonaws.com', :srv3

set :user, 'ec2-user'
ssh_options[:keys] = KEY_FILE

task :uname_all do
  run "uname -a"
end

task :uname_srv1, :roles => :srv1 do
  run "uname -a"
end

task :uname_srv2, :roles => :srv2 do
  run "uname -a"
end