vagrantにphpmyadminを導入したところmysqlにrootログインできなくなりました。

vagrantにphpadminを設置したのですが、それ以降mysqlにrootでログインできなくなりました。ネットの記事をコピペしながらどこをどう変更したのか覚えていません。記憶の中で定かなのはおそらくホスト名をデフォルトから変えた、vimでなにかをコピペして保存した、などのようなことです。検索して出てくるrootログインが出来ない場合の対処はしました。
現状は

mysql -u root 
```を実行すると

ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)

が帰ってきて、

mysqld --skip-grant-tables

でもログインできないです。
どこがおかしいのでしょうか？

```vagrantfile
// -*- mode: ruby -*-
// vi: set ft=ruby :
// All Vagrant configuration is done below. The "2" in Vagrant.configure
// configures the configuration version (we support older styles for
// backwards compatibility). Please don't change it unless you know what
// you're doing.

Vagrant.configure("2") do |config|
  // The most common configuration options are documented and commented below.
  // For a complete reference, please see the online documentation at
  // https://docs.vagrantup.com.

  // Every Vagrant development environment requires a box. You can search for
  // boxes at https://vagrantcloud.com/search.
  config.vm.box = "bento/centos-6.8"

  // Disable automatic box update checking. If you disable this, then
  // boxes will only be checked for updates when the user runs
  // `vagrant box outdated`. This is not recommended.
  // config.vm.box_check_update = false

  // Create a forwarded port mapping which allows access to a specific port
  // within the machine from a port on the host machine. In the example below,
  // accessing "localhost:8080" will access port 80 on the guest machine.
  // NOTE: This will enable public access to the opened port
  // config.vm.network "forwarded_port", guest: 80, host: 8080

  // Create a forwarded port mapping which allows access to a specific port
  // within the machine from a port on the host machine and only allow access
  // via 127.0.0.1 to disable public access
  // config.vm.network "forwarded_port", guest: 80, host: 8080, host_ip: "127.0.0.1"

  // Create a private network, which allows host-only access to the machine
  // using a specific IP.
  config.vm.hostname = "my.localhost"
  config.vm.network "private_network", ip: "192.168.33.10"

  // Create a public network, which generally matched to bridged network.
  // Bridged networks make the machine appear as another physical device on
  // your network.
  // config.vm.network "public_network"

  // Share an additional folder to the guest VM. The first argument is
  // the path on the host to the actual folder. The second argument is
  // the path on the guest to mount the folder. And the optional third
  // argument is a set of non-required options.
  config.vm.synced_folder "C:/Users/(自分の名前)/PhpstormProjects", "/home/vagrant" , type:"virtualbox"

  // Provider-specific configuration so you can fine-tune various
  // backing providers for Vagrant. These expose provider-specific options.
  // Example for VirtualBox:
  //
  // config.vm.provider "virtualbox" do |vb|
  //    Display the VirtualBox GUI when booting the machine
  //   vb.gui = true
  //
  //    Customize the amount of memory on the VM:
  //   vb.memory = "1024"
  // end
  //
  // View the documentation for the provider you are using for more
  // information on available options.

  // Enable provisioning with a shell script. Additional provisioners such as
  // Puppet, Chef, Ansible, Salt, and Docker are also available. Please see the
  // documentation for more information about their specific syntax and use.
  // config.vm.provision "shell", inline: <<-SHELL
  //   apt-get update
  //   apt-get install -y apache2
  // SHELL
end

ps.一つ気になるのはホスト名をもとに戻そうとvagrantfileのconfig.vm.hostname = "my.localhost"をコメントアウトしてみたのですがputty上で[vagrant@my~]$としか出でない（vagrantfileが反映されていない？本来なら初期状態の@localhostになるかと思ったのですが）