Linux mount/unmount Commands (6/16)

Linux is an excellent open-source operating system, can run in large-to-small to the palm of a variety of computer systems, with the growing maturity and stability of Linux systems and its unique advantages of open source code, Linux in the world has been more and more widely used. Nowadays, many enterprises ' computer systems are mixed systems composed of UNIX system, Linux system and Windows system, and data exchange between different systems is often needed. I'll show you how to mount a CD image file, a removable hard disk, a USB flash drive, and a Windows network share and UNIX NFS network share on a Linux system, based on my actual work experience.

Hook up Command (Mount)

Among the parameters commonly used are:
-A installs all file systems that are class-out in the/etc/fstab file.
-F disguises mount, making checks on the device and the directory look, but does not really mount the file system.
-N does not record the installation in the/etc/mtab file.
-R tells the file system to be installed as read-only.
-V Displays the installation information in detail.
-W installs the file system as writable, by default for the command:

Command format:

Mount [-t vfstype] [-O options] Device dir

which

1.-t vfstype Specifies the type of file system that is not normally specified. Mount will automatically select the correct type. Common types are:

Disc or disc Image: iso9660

Mount Windows file network share: SMBFS

EXT2 Linux currently used file system

Msdos MS-DOS FAT, is FAT16
VFAT Windows98 commonly used FAT32
NFS Network File System UNIX (LINUX) file network share
ISO9660 CD-ROM standard file system
File system for NTFS Windows NT/2000/XP
Auto automatically detects the file system

The 2.-o options are primarily used to describe the way devices or files are hooked up. The commonly used parameters are:

-o Specifies the option to mount the file system, and some can also be written to the/etc/fstab. Commonly used are:
Defaults Use default values for all options (auto, Nouser, RW, suid)
Auto/noauto Allow/disallow installation with the –A option
Dev/nodev/Do not interpret special devices on file systems
Exec/noexec Allow/Disallow binary code execution
Suid/nosuid Confirm/Not confirm suid and Sgid bit
User/nouser Allow/Disallow normal users to mount
CODEPAGE=XXX code page
Iocharset=xxx Character Set
RO mount in read-only mode
RW mount in read-write mode
Remount Reinstall a file system that has already been installed

Loop: Used to attach a file as a hard disk partition on the system

Iocharset: Specifies the character set used to access the file system

3.device the device to mount (Mount).

Mount point of the 4.dir device on the system.

Mount Disc image File

Due to the huge advances in disk technology in recent years, new computer systems are equipped with large-capacity disk systems, and many people in windows are accustomed to using the software and materials as disc image files through a virtual optical drive. This has many advantages: first, to reduce the wear of the optical drive; second, the hard disk capacity to store dozens of CD image files is not a problem, with the use of Tiaogan is very convenient; third, the hard disk reading speed is much higher than the optical disk reading speed, the CPU occupancy rate is greatly reduced. In fact, it is more convenient to make and use optical disk images in Linux than for Windows, without borrowing any third-party packages.

1. Make disc image file from CD-ROM. Put the disc in the CD drive and execute the command below.

#cp/dev/cdrom/home/sunky/mydisk.iso or

#dd If=/dev/cdrom Of=/home/sunky/mydisk.iso

Note: Any of the above commands can be used to make discs in the current optical drive into a disc image file/home/sunky/mydisk.iso

2. Make the files and directories into a disc image file, execute the following command.

#mkisofs-R-j-v Mydisk-o/home/sunky/mydisk.iso/home/sunky/mydir

Note: This command makes all directories and files in the/home/sunky/mydir directory into a disc image file/home/sunky/mydisk.iso, the disc is labeled: Mydisk

3. Mounting of the disc image file (Mount)

#mkdir/mnt/vcdrom

Note: Create a directory to use as a mount point

#mount-O loop-t iso9660/home/sunky/mydisk.iso/mnt/vcdrom

Note: You can access all the files in the disk image file Mydisk.iso using/mnt/vcdrom.

Hooking up a removable hard disk

For Linux systems, the USB interface's removable hard disk is treated as a SCSI device. Before inserting a removable hard disk, you should first use Fdisk–l or more/proc/partitions to view the system's hard disk and hard disk partition.

[Root at Pldyrouter/]# fdisk-l

disk/dev/sda:73 Dot 4 GB, 73407820800 bytes

255 heads, Sectors/track, 8924 cylinders

Units = Cylinders of 16065 * 8225280 bytes

Device Boot Start End Blocks Id System

/DEV/SDA1 1 4 32098+ de Dell Utility

/DEV/SDA2 * 5 2554 20482875 7 Hpfs/ntfs

/dev/sda3 2555 7904 42973875-up Linux

/DEV/SDA4 7905 8924 8193150 f Win95 Ext ' d (LBA)

/dev/sda5 7905 8924 8193118+, Linux swap

Here you can see clearly that the system has a SCSI hard disk/DEV/SDA and its four disk partitions/dev/sda1-/DEV/SDA4,/DEV/SDA5 is the logical partition/DEV/SDA4 partition. After the removable hard drive, then use Fdisk–l or more/proc/partitions to view the system's hard disk and hard disk partition situation

[Root at Pldyrouter/]# fdisk-l

disk/dev/sda:73 Dot 4 GB, 73407820800 bytes

/DEV/SDC5 511 4864 34973473+ b Win95 FAT32

You should be able to find a SCSI hard disk/DEV/SDC and its two disk partitions/dev/sdc1?,/DEV/SDC2, where/DEV/SDC5 is the logical partition of the/DEV/SDC2 partition. We can use the following command to hook up/DEV/SDC1 and/DEV/SDC5.

#mkdir-P/MNT/USBHD1

#mkdir-P/MNT/USBHD2

Note: Create a directory to use as a mount point

#mount-T NTFS/DEV/SDC1/MNT/USBHD1

#mount-T VFAT/DEV/SDC5/MNT/USBHD2

Note: For NTFS-formatted disk partitions, you should use the-T NTFS parameter, and the-T VFAT parameter should be used for disk partitions in FAT32 format. If the kanji file name is displayed as garbled or not displayed, you can use the following command format.

#mount-T Ntfs-o iocharset=cp936/dev/sdc1/mnt/usbhd1

#mount-T Vfat-o iocharset=cp936/dev/sdc5/mnt/usbhd2

Using the Fdisk partitioning command and the Mkfs file system creation command under the Linux system, the partition of the removable hard disk can be made into the ext2, ext3 format peculiar to the Linux system. This makes it easier to use under Linux. Use the following command to hook up directly.

#mount/DEV/SDC1/MNT/USBHD1

Mount USB flash Drive

As with the USB interface of a removable hard disk, the USB stick is also treated as a SCSI device for Linux systems. Use the same method as moving the hard disk. Before inserting a USB flash drive, you should first use Fdisk–l or more/proc/partitions to view the system's hard disk and hard disk partition.

[Root at Pldyrouter root]# fdisk-l

disk/dev/sda:73 Dot 4 GB, 73407820800 bytes

255 heads, Sectors/track, 8924 cylinders

/dev/sda5 7905 8924 8193118+, Linux swap

After inserting the USB drive, use Fdisk–l or more/proc/partitions to view the system's hard disk and hard disk partition.

[Root at Pldyrouter root]# fdisk-l

disk/dev/sda:73 Dot 4 GB, 73407820800 bytes

phys= (+, 8, logical=) (888, 7, 31)

The system has a SCSI hard disk/DEV/SDD and a disk partition/DEV/SDD1,/DEV/SDD1 is the USB stick we want to hook up.

#mkdir-P/MNT/USB

Note: Create a directory to use as a mount point

#mount-T Vfat/dev/sdd1/mnt/usb

Note: You can now access the USB flash drive through/MNT/USB, if the Chinese character file name is displayed as garbled or not displayed, you can use the following command.

#mount-T Vfat-o iocharset=cp936/dev/sdd1/mnt/usb

Hooking up Windows file shares

The core of Windows network sharing is smb/cifs, where you have to install and use the Samba package if you want to mount a disk share for Windows on Linux. The majority of popular Linux distributions now contain samba packages, and if you install a Linux system without samba, install Samba first. Of course, you can also download the www.samba.org website ... The new version is 3.0.10 version.

When the Windows system share is set up, you can hook up (mount) on the Linux client, with the following details:

# Mkdir–p/mnt/samba

Note: Create a directory to use as a mount point

# mount-t Smbfs-o username=administrator,password=pldy123//10.140.133.23/c$/mnt/samba

Note: Administrator and pldy123 are a user name and password for the IP address of the 10.140.133.23 Windows computer, and C $ is a disk share on this computer

This allows you to access the files on the Windows system disk via/mnt/samba on your Linux system. These actions are tested in Redhat as server 3, Redflag Server 4.1, SuSE Server 9, and Windows NT 4.0, Windows 2000, Windows XP, Windows 2003 environments.

Hooking up UNIX System NFS file shares

Similar to the Windows-based network share, UNIX (Linux) systems also have their own network shares, that is, NFS (Network File system), below we are in the Sun Solaris2.8 and Redhat as server 3 For example, briefly describe how to mount an NFS network share under Linux.

Before the Linux client mounts (Mount) NFS disk share, the NFS server must be configured first.

1. The Solaris system NFS Server configuration method is as follows:

(1) Modify/etc/dfs/dfstab, add shared directory

Share-f Nfs-o Rw/export/home/sunky

(2) Start the NFS service

#/etc/init.d/nfs.server Start

(3) After the NFS service is started, you can also use the following command to add a new share

# Share/export/home/sunky1

# Share/export/home/sunky2

Note:/export/home/sunky and/export/home/sunky1 are directories that are ready to be shared

2, the Linux system NFS server configuration method is as follows:

(1) Modify/etc/exports, add shared directory

/export/home/sunky 10.140.133.23 (rw)

/export/home/sunky1 * (rw)

/export/home/sunky2 linux-client (rw)

Note: Sunky, Sunky1, sunky2 in the/export/home/directory are the directories that are ready to be shared, 10.140.133.23, *, and linux-client are the IP addresses or host names that are allowed to hook up this shared Linux client. If you want to use hostname linux-client You must add the Linux-client host IP definition in the server host/etc/hosts file. The format is as follows:

10.140.133.23 linux-client

(2) Start and stop NFS services

/etc/rc.d/init.d/portmap Start (Portmap is started by default in Redhat)

/etc/rc.d/init.d/nfs Start NFS Service

/etc/rc.d/init.d/nfs Stop Stop NFS Service

Note: If you modify the/etc/export file to add new shares, you should stop the NFS service before starting the NFS service to make the newly added share work. The same effect can be achieved using the command EXPORTFS-RV.

3, Linux client mount (Mount) NFS sharing for other Linux systems or UNIX systems

# Mkdir–p/mnt/nfs

Note: Create a directory to use as a mount point

#mount-t Nfs-o RW 10.140.133.9:/export/home/sunky/mnt/nfs

Note: Here we assume that 10.140.133.9 is the host IP address of the NFS server, of course, the host name can be used here, but the server-side IP definition must be added to the native/etc/hosts file. /export/home/sunky the directory that is shared with the server.

This allows the Linux client to access files that are shared on NFS by other Linux systems or UNIX systems via/MNT/NFS. These actions are tested in Redhat as Server 3, Redflag server4.1, SuSE Server 9, and Solaris 7, Solaris 8, and Solaris 9 for X86&SPARC environments.

Permissions issues:

Server-side user jack, user ID 1818, GID for 1818, client side also has a user jack, but UID and GID is 1818. The client-side Jack wants to fully read the server-side/home/jack. The server-side/etc/exports is

Write this:

/home/jack * (rw,all_squash,anonuid=1818,anongid=1818)

This setup means that all client-side users access the server-side/home/jack this

When it is recorded, it will map to the server-side Jack (uid,gid=1818). My mount's results are

1. Client-side root can be fully accessed, including reading, writing, killing ... such as

2. The client side of Jack (uid,gid=1818) I can do:

RM-RF server_jack/*
CP Something server_jack/
mkdir server_jack/a

Note that the mount point must be a directory that already exists, this directory may not be empty, but the previous contents of this directory will not be available after mounting, Umount will return to normal later. When using multiple-o parameters,-O is used only once, and the parameters are separated by commas:

CODE:
# Mount–o REMOUNT,RW/
For example, to mount the file system in Windows FAT32 D-disk, generally under Linux this partition corresponds to/dev/hda5, depending on the specific partition situation will be different, here is hda5 to illustrate:
CODE:
# MKDIR/MNT/HDA5//Create hda5 directory as mount point, location and directory name can be customized//
# mount-t Vfat/dev/hda5/mnt/hda5
In general, Linux automatically detects the file system of a partition, unless you specify it, the-t vfat can be omitted.
CODE:
# MOUNT/DEV/HDA5/MNT/HDA5
This allows access to the/MNT/HDA5 directory for resources in the partition.
3. Why does the partition on Mount not display Chinese file as question mark/garbled?
Display a question mark indicating that there is no recognizable Chinese font in your system, please install the Chinese font first. Make sure your system is already well-displayed in Chinese. Shown as garbled is generally caused by the file system encoding used by the mount default and the actual encoding inconsistencies in the file system. To display Chinese files normally, mount requires the codepage and Iocharset options in the-o parameter. CODEPAGE specifies the code page of the file system, the Chinese code is 936;iocharset specified character set, Simplified Chinese is generally used cp936 or gb2312.
CODE:
# Mount–o iocharset=gb2312 Codepage=936/dev/hda5/mnt/hda5
Generally speaking, mount–o iocharset=cp936/dev/hda5/mnt/hda5 can solve the problem.
If you have problems with this, try UTF-8 encoding:
CODE:
# Mount–o Iocharset=utf8/dev/hda5/mnt/hda5
4. Why is the partition normal user not writable after mount up?
Mount with –o umask=000:
CODE:
# Mount–o umask=000, Iocharset=cp936/dev/hda5/mnt/hda5
5. Why did the files in the partition after mount go into short filenames?
This is the reason why the file system hangs wrong, when the FAT32 is mounted as FAT16, this happens, first Umount, and then re-mount with –t vfat to solve the problem.
CODE:
# mount–t Vat/dev/hda5/mnt/hda5
6. Why can't I mount an NTFS partition?
This is why the kernel does not support the NTFS file system, please recompile the kernel or install the NTFS file system support package for the kernel so that the kernel has NTFS file system support.
7. How do I mount a USB stick and mp3?
If the computer does not have other SCSI devices and USB peripherals, the device path of the inserted USB drive is/dev/sda1, using the command:
CODE:
# mkdir/mnt/u
# mount/dev/sda1/mnt/u
Mount it.
8. Can I use the ISO file directly?
Yes, this option for mount makes it possible to have a free virtual optical drive under Linux, with the following specific usage:
CODE:
# Mkdir/mnt/iso
# Mount–o Loop Linux.iso/mnt/iso
Of course, mounting the mount point/mnt/iso is also read-only.
9. How can I not mount an ISO file?
In general, the kernel used by most distributions has compiled support for the loop device, but there is no case, so make sure that the kernel used by the system supports the loop device.
The second case is that the ISO file is placed in NTFS or other read-only file systems. The Mount loop device must be mounted to a writable partition, and currently the Linux kernel has very limited write support for the NTFS file system, please copy the ISO file to another writable file system before mounting.
10. How to mount the optical driveand floppy
Generally CDROM device file is/DEV/HDC, the device name of the floppy drive is/dev/fd0
CODE:
# Mkdir/mnt/cdrom
# Mount/dev/hdc/mnt/cdrom//Mount Optical Drive//
# Mkdir/mnt/floppy
# Mount/dev/fd0/mnt/floppy//Mount Floppy//
11. Why does the attached CD-ROM not display Chinese files?
Using the –o iocharset=cp936 option will generally solve the problem, otherwise use utf-8 encoding.
CODE:
# Mount–o Iocharset=cp936/dev/hdc/mnt/cdrom
12. How do I automatically mount partitions on boot?
It is cumbersome to enter such a long command for each mount, as long as the partition information is written to the/etc/fstab file to automatically mount the system boot, for example, to add the following line to the/DEV/HDA5 auto mount:
CODE:
/dev/hda5/mnt/hda5 vfat defaults,iocharset=cp936, rw 0 0
13. How can I mount a samba partition?
CODE:
# Mkdir/mnt/share
# mount-t Smbfs-o Username=root,password=abc,codepage=936,iocharset=gb2312//192.168.1.100/share/mnt/share
If the Chinese display is not normal, try UTF-8 encoding. Of course, you can write to the fstab to implement automatic mounting.
What does mount--bind mean?
Mount--bind is to mount the contents of one directory to another directory, using the
CODE:
# mount--bindOlddir Newdir
This command makes it especially convenient for you to set up FTP to share a directory. If you want to cancel the Mount command:
CODE:
# mount--moveOlddir Newdir can be.
If Mount--bind also wants to write to Fstab, the format is as follows:
CODE:
Olddir newdir None bind 0 0
What is the basic usage of umount?
For example,/DEV/HDA5 has been mounted on the/MNT/HDA5, using three commands can be uninstalled mounted file system
CODE:
# UMOUNT/DEV/HDA5
# UMOUNT/MNT/HDA5
# UMOUNT/DEV/HDA5/MNT/HDA5
16. Why does the Umount show device busy?
This is because there is a program is accessing the device, the simplest way is to let the program to access the device to quit and then Umount. There may be times when users do not clear exactly what program is accessing the device, and if the user is not anxious to umount, it can be used:
CODE:
# umount-l/mnt/hda5
To uninstall the device. The option –l is not immediately umount, but umount after the directory is idle. You can also use the command PS aux to see the device's program PID, and then use the command kill to kill the process of occupying the device, so umount very relieved.

Method One:
Fuser-m-v/nfs_old/
User Process number Permission command
/nfs_old/: Root 2699. C.. bash
Root 2999.. C.. su
As shown above, there are two processes occupied, kill them, and then cancel the mount again.
Kill-9 2699 2999
umount/nfs_old/

Method Two:
Umount-l/nfs_old/

Method Three:
fuser-km/nfs_old/

Linux mount/unmount Command (6/16)