/etc/fstab 是专门用配置挂载硬盘的文件

语法为：

[Device] [Mount Point] [File System Type] [Options] [Dump] [Pass]

详细解释为:

<device>	The device/partition (by /dev location or UUID) that contain a file system.
<mount point>	The directory on your root file system (aka mount point) from which it will be possible to access the content of the device/partition (note: swap has no mount point). Mount points should not have spaces in the names.
<file system type>	Type of file system
<options>	Mount options of access to the device/partition (see the man page for mount).
<dump>	Enable or disable backing up of the device/partition (the command dump). This field is usually set to 0, which disables it.
<pass num>	Controls the order in which fsck checks the device/partition for errors at boot time. The root device should be 1. Other partitions should be 2, or 0 to disable checking.

第一列和第二列的device 和 mount point 顾名思义，就是你想要挂载的device  和挂载的位置.

device 有两种表示方式，可以用/dev/xdx 之类的location 或者 硬件的UUID 来表示，硬件的UUID 可以用blkid 来查询

第三列的file system type 也很好理解，这里一般有auto, vfat( for FAT partition), ntfs or ntfs-3g( for NTFS partition), ext4 or ext3 or ext2 or jfs,  udf or iso9660 ( for CD/DVD), swap

第四列的option，一般用默认的defaults，但是也可以使用下面的option:

sync/async - All I/O to the file system should be done (a)synchronously.
auto - The filesystem can be mounted automatically (at bootup, or when mount is passed the -a option). This is really unnecessary as this is the default action of mount -a anyway.
noauto - The filesystem will NOT be automatically mounted at startup, or when mount passed -a. You must explicitly mount the filesystem.
dev/nodev - Interpret/Do not interpret character or block special devices on the file system.
exec / noexec - Permit/Prevent the execution of binaries from the filesystem.
suid/nosuid - Permit/Block the operation of suid, and sgid bits.
ro - Mount read-only.
rw - Mount read-write.
user - Permit any user to mount the filesystem. This automatically implies noexec, nosuid,nodev unless overridden.
nouser - Only permit root to mount the filesystem. This is also a default setting.
defaults - Use default settings. Equivalent to rw, suid, dev, exec, auto, nouser, async.
_netdev - this is a network device, mount it after bringing up the network. Only valid with fstype nfs.

第五列 dump，dump 是linux 系统中的一个备份工具，用0 来表示不备份这个区，1 表示备份。这里不适合长篇大论来讨论dump 和 fsck ，但是通过查看/etc/fstab 的例子可以看到，第五列的选项一般为0

第六列 fsck 表示fsck 是否会check这个区，一般用1 来表示根分区， 2 表示其他的分区；0表示不检查

对于第5,6列来说，

/ 一般为1 1

swap 一般为 0 0

其他分区一般为1 2

云硬盘可谓0 2