vagrantの起動について

vagrantが突然起動しなくなりました。
1度起動したのですが、2回目に起動させようとしたらエラーになり、原因がわからず困っております。
どなたかわかるかたいらっしゃいましたら教えてください。

■環境
Vagrant 1.9.3
ubuntu 16.04
VirtualBox 5.1.22

エラー内容
#vagrant up

Bringing machine 'default' up with 'virtualbox' provider...
==> default: Clearing any previously set forwarded ports...
==> default: Clearing any previously set network interfaces...
==> default: Preparing network interfaces based on configuration...
    default: Adapter 1: nat
==> default: Forwarding ports...
    default: 22 (guest) => 2222 (host) (adapter 1)
==> default: Running 'pre-boot' VM customizations...
==> 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: ivilinux
    default: SSH auth method: private key
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.

インターネットで検索するとsshの設定のようなことが書いてあったので、sshの設定を調べようとしたのですが、
そこでもエラーになりました。
エラー内容は下記です。

#vagrant ssh-config
The provider for this Vagrant-managed machine is reporting that it
is not yet ready for SSH. Depending on your provider this can carry
different meanings. Make sure your machine is created and running and
try again. Additionally, check the output of `vagrant status` to verify
that the machine is in the state that you expect. If you continue to
get this error message, please view the documentation for the provider
you're using.

また別件なのですが、VirtualBoxでブリッジでインターネットを接続する手順は下記でよろしいでしょうか？
「設定」-「ネットワーク」-「アダプター１」の「割り当て」をNATからブリッジアダプターに変更