先ほどまでずっとvagrant sshの状態でsassを使い遊んでいて、新しいタブで効率よくしようと思い2個ほど新しくターミナルを開いたらていつものようにvagrant upをしたら

> 
==> default: Checking if box 'chef/centos-6.5' is up to date...
==> default: Resuming suspended VM...
==> default: Booting VM...
==> default: Waiting for machine to boot. This may take a few minutes...
    default: SSH address: 127.0.0.1:2222
    default: SSH username: vagrant
    default: SSH auth method: private key
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
    default: Warning: Connection timeout. Retrying...
Timed out while waiting for the machine to boot. This means that
Vagrant was unable to communicate with the guest machine within
the configured ("config.vm.boot_timeout" value) time period.
>
If you look above, you should be able to see the error(s) that
Vagrant had when attempting to connect to the machine. These errors
are usually good hints as to what may be wrong.
>
If you're using a custom box, make sure that networking is properly
working and you're able to connect to the machine. It is a common
problem that networking isn't setup properly in these boxes.
Verify that authentication configurations are also setup properly,
as well.
>
If the box appears to be booting properly, you may want to increase
the timeout ("config.vm.boot_timeout") value.

こんなエラーが出ました。当然vagrant sshもできずにエラーが出ます

ssh_exchange_identification: Connection closed by remote host

後、気になった症状といえばsassで何十回か変換した後に何も動かなくなったことです。順番的に言えば急に動かなくなったと同時に新しいタブを開きました。
ドットインストールを参考に導入しました。
ゲストからの質問で恐縮ですが、何卒よろしくお願いします。