capistrano3 - First deploy fails in Capistrano 3 with a /var/www/XXX permission error -

i running first deploy machine via cap staging deploy. of cap3, deploy:setup no longer needed. yet, strangely, mkdir permissions error:

 info[cb348f12] running /usr/bin/env mkdir -pv /var/www/myapp/shared /var/www/myapp/releases on ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com  debug[cb348f12] command: /usr/bin/env mkdir -pv /var/www/myapp/shared /var/www/myapp/releases  debug[cb348f12]    mkdir:   debug[cb348f12]    cannot create directory ‘/var/www’  debug[cb348f12]    : permission denied  debug[cb348f12]      debug[cb348f12]    mkdir:   debug[cb348f12]    cannot create directory ‘/var/www’  debug[cb348f12]    : permission denied  debug[cb348f12]      cap aborted!  sshkit::runner::executeerror: exception while executing on host ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com: mkdir exit status: 1 

of course, go create , chmod directory myself, that's not point. cap3 supposed take care of itself. i'm confused why doesn't that. should note had same setup succeed before machine (though "production" environment).

here basic settings in deploy.rb:

 set :application, "myapp"  set :user, 'ec2-user' 

instead of creating following directory structure: /var/www/myapp/shared/var/www/myapp/releases try: /var/www/myapp/releases