Mount and Unmount¶
Intro¶
After the file system is set up, devices cannot be used until mounted.
Windows and macOS can mount automatically.
Linux without desktop environment or other services will not mount on their own.
It is advised to use /mnt
directory. But there is no restrictions.
Some disks should be mounted at /
Some details about root mount (see highest voted answer)
Commands¶
mount
mount # display mount information
mount /dev/sda3 /mnt # device-to-mount point-to-mount
(Read man page for more details)
-t
- Specify the file system type
- When failed to recognize automatically
-o [options]
- remount
- re mount
- must remount if wish to change the mount options
- ro/rw
- read only
- read write (default)
- sync
- disable cache, all operations are written directly to disk
- Linux usually write changes into cache (in memory) and write to disks when the system is idle
- may be safer but slower
- only necessary when the power is very unstable and the data are very important
- disable cache, all operations are written directly to disk
- async
- enable cache (default)
- noatime
- do not update the access time of accessed files
- improve efficacy especially with high disk operations frequency
- atime
- access time
- update access time (default)
- Use commas (,) to separate different flags in one command
umount
umount <some-device>
umount <some-mount-points>
un mount
Must unmount before any operations on file systems.
Handle Busy Device¶
fuser
fuser -m <some-mount-point>
file user
Check which process is using given mount point
lsof
lsof <some-path>
list open file
list the files that are being used
Auto Mount at Boot¶
/etc/fstab
file systems table file
Lines begin with # are comments
Each line (in 5 parts) represents a auto-mount config:
- The device to mount
- e.g. /dev/sda3
LABEL=XXX
can be used to replace/dev/sda3
- UUID can also be used
- The mount point
- File system
- Mount Options (see above)
- e.g. defaults
- Options for dump and fsck
- e.g. 0 0
- Usually no need to change
Use Tab
to format
mount -a
can be used to mount fstab