【linux之挂载，Raid，LVM】

mount [options] [-o options] DEVICE MOUNT_POINT
设备：
设备文件：/dev/sda5
卷标：LABEL=""
UUID: UUID=""
挂载点：目录
要求：
、此目录没有被其他进程使用；
、目录得事先存在；
、目录中的原有的文件将会暂时隐藏；
选项：
-a:表示挂载/etc/fstab文件中定义的所有文件系统
-n：默认情况下，mount命令每挂载一个设备，都会把挂载的设备信息保存到/etc/mtab.加了-n就不写入/etc/mtab中
-r：以只读方式挂载
-w：以读写的方式挂载
-L:指明卷标
-U:用UUID挂载
-t：指明文件系统类型，默认通过blkid来识别指定
-o：指定挂载时候选项的内容
async All I/O to the filesystem should be done asynchronously. (See also the sync option.) atime Update inode access time for each access. See also the strictatime mount option. noatime
Do not update inode access times on this filesystem (e.g, for faster access on the news spool
to speed up news servers). auto Can be mounted with the -a option. noauto Can only be mounted explicitly (i.e., the -a option will not cause the filesystem to be
mounted). context=context, fscontext=context, defcontext=context and rootcontext=context
The context= option is useful when mounting filesystems that do not support extended
attributes, such as a floppy or hard disk formatted with VFAT, or systems that are not nor-
mally running under SELinux, such as an ext3 formatted disk from a non-SELinux workstation.
You can also use context= on filesystems you do not trust, such as a floppy. It also helps in
compatibility with xattr-supporting filesystems on earlier 2.4.<x> kernel versions. Even where
xattrs are supported, you can save time not having to label every file by assigning the entire
disk one security context. A commonly used option for removable media is context=system_u:object_r:removable_t. Two other options are fscontext= and defcontext=, both of which are mutually exclusive of the
context option. This means you can use fscontext and defcontext with each other, but neither
can be used with context. The fscontext= option works for all filesystems, regardless of their xattr support. The fscon-
text option sets the overarching filesystem label to a specific security context. This
filesystem label is separate from the individual labels on the files. It represents the entire
filesystem for certain kinds of permission checks, such as during mount or file creation.
Individual file labels are still obtained from the xattrs on the files themselves. The context
option actually sets the aggregate context that fscontext provides, in addition to supplying
the same label for individual files. You can set the default security context for unlabeled files using defcontext= option. This
overrides the value set for unlabeled files in the policy and requires a filesystem that sup-
ports xattr labeling. The rootcontext= option allows you to explicitly label the root inode of a FS being mounted
before that FS or inode because visable to userspace. This was found to be useful for things
like stateless linux. For more details, see selinux() defaults
Use default options: rw, suid, dev, exec, auto, nouser, and async. dev Interpret character or block special devices on the filesystem. nodev Do not interpret character or block special devices on the file system. diratime
Update directory inode access times on this filesystem. This is the default. nodiratime
Do not update directory inode access times on this filesystem. dirsync
All directory updates within the filesystem should be done synchronously. This affects the
following system calls: creat, link, unlink, symlink, mkdir, rmdir, mknod and rename. exec Permit execution of binaries. noexec Do not allow direct execution of any binaries on the mounted filesystem. (Until recently it
was possible to run binaries anyway using a command like /lib/ld*.so /mnt/binary. This trick
fails since Linux 2.4. / 2.6..) group Allow an ordinary (i.e., non-root) user to mount the filesystem if one of his groups matches
the group of the device. This option implies the options nosuid and nodev (unless overridden
by subsequent options, as in the option line group,dev,suid). iversion
Every time the inode is modified, the i_version field will be incremented. noiversion
Do not increment the i_version inode field. mand Allow mandatory locks on this filesystem. See fcntl().
All directory updates within the filesystem should be done synchronously. This affects the
following system calls: creat, link, unlink, symlink, mkdir, rmdir, mknod and rename. nomand Do not allow mandatory locks on this filesystem. _netdev
The filesystem resides on a device that requires network access (used to prevent the system
from attempting to mount these filesystems until the network has been enabled on the system). nofail Do not report errors for this device if it does not exist. relatime
Update inode access times relative to modify or change time. Access time is only updated if
the previous access time was earlier than the current modify or change time. (Similar to noat-
ime, but doesn’t break mutt or other applications that need to know if a file has been read
since the last time it was modified.) norelatime
Do not use relatime feature. See also the strictatime mount option. strictatime
Allows to explicitly requesting full atime updates. This makes it possible for kernel to
defaults to relatime or noatime but still allow userspace to override it. For more details
about the default system mount options see /proc/mounts. nostrictatime
Use the kernel’s default behaviour for inode access time updates. suid Allow set-user-identifier or set-group-identifier bits to take effect. nosuid Do not allow set-user-identifier or set-group-identifier bits to take effect. (This seems
safe, but is in fact rather unsafe if you have suidperl() installed.) owner Allow an ordinary (i.e., non-root) user to mount the filesystem if he is the owner of the
device. This option implies the options nosuid and nodev (unless overridden by subsequent
options, as in the option line owner,dev,suid). remount 重新挂载
Attempt to remount an already-mounted filesystem. This is commonly used to change the mount
flags for a filesystem, especially to make a readonly filesystem writeable. It does not change
device or mount point.