vagrantのBoxを追加

$ vagrant box add new_test_box appname_YYYYMMDD.box
$ vagrant init new_test_box
$ vi Vagrantfile
$ vagrant up

default: Warning: Authentication failure. Retrying...
default: Warning: Authentication failure. Retrying...
default: Warning: Authentication failure. Retrying...

$ vagrant ssh-config
$ ssh-keygen -yf C:/Users/<ユーザー名>/.vagrant.d/insecure_private_key > public_key
$ cat public_key # ←ここの内容を
$ vagrant ssh
[vagrant@localhost ~]$ vi ~/.ssh/authorized_keys # ←ここで書き換える
[vagrant@localhost ~]$ exit
$ vagrant reload

参考
http://qiita.com/d2cdot-mmori/items/1c340f175ae510e4456a
感謝