ubuntu 使用dm-crypt 加密目录，并且开机自动加载

gistfile1.txt

=========== 文件磁盘========

---- init ----
#安装依赖
sudo apt-get install cryptsetup


#虚拟磁盘并格式化
sudo fallocate -l 512M /root/home
sudo cryptsetup -y luksFormat /root/home


# 添加keyfile
dd if=/dev/urandom of=/root/keyfile bs=1 count=256
sudo cryptsetup luksAddKey /root/home /root/keyfile


#打开虚拟磁盘
sudo cryptsetup luksOpen /root/home home --key-file /root/keyfile

#格式化
sudo mkfs.ext4 -j /dev/mapper/home

# 挂在
sudo mount /dev/mapper/home /mnt/home




------ close ----

sudo umount /mnt/home

sudo cryptsetup luksClose home



---- reopen ----

sudo cryptsetup luksOpen /root/home home

sudo mount /dev/mapper/home /mnt/home


---  auto mount ---
# /etc/fstab 添加如下
# <file system>    <mount point>   <type>   <options>   <dump>  <pass>
/dev/mapper/home   /mnt/home           ext4     defaults    1       2


# etc/crypttab 添加如下
# <target name>	<source device>		<key file>	<options>
home          /root/home         /root/keyfile         luks