Disk and File System Management (II)

I. File system

1. You cannot create a file system on a partition that already has files that can corrupt an existing file

2. Create a file system on a partition

A.cat/proc/filesystems View the file system types supported by the current kernel

B.cat/proc/partitions View all partition information for the current system

C.MKFS command--Create a file system

Mkfs-t Ext3/dev/sda5

-T: Specify File system type

Mkfs-t ext2 = mkfs.ext2

Specialized in managing EXT series files:

Mke2fs

-j: Create ext3 Type file system (default to create Ext2 file system)

-B block_size: Specifies the block size, default is 4096; available values are 1024, 2048, or 4096

-L LABEL: Specifies the partition volume label (partition name)

-M #: Specifies the percentage of blocks reserved for super users

-I #: To specify how many bytes of space to create an inode, the default is 8192; The value given here should be 2^n times the block size

-N #: Specify Inode Count

-F: Force a file system to be created (for cases where the file system is already mounted)

-E: User Specifies additional file system properties

Blkid: Querying or viewing related properties of disk devices

Usage: Blkid/dev/sda3

UUID: A uniform global identifier

Type: File system types

Label: The volume label of the partition

E2label: Used to view or define volume labels

E2label device File View Volume label

E2label device File volume label set volume label

TUNE2FS: Adjust file system related properties (created file system can no longer resize blocks)

-j: Upgrade ext2 to ext3 without compromising the original data

-L LABEL: Set or modify volume label

-M #: adjust reserve percentage

-R #: Specify the number of reserved blocks

-O: Set default mount Options

ACL functionality

-C #: Specify the number of mounts to # times after the self-test, 0 or 1 tables turn off this feature

-I #: self-Test on how many days each mount is used; 0 or 1 means turn off this feature

-L: Displays information in the Super block

DUMPE2FS: Displaying file system Property information

-H: Show only information in the Super block

Fsck: Checking and repairing the Linux file system

-T Fstype: Specifying the file system type

-A: Automatic repair

E2FSCK: Dedicated to repairing Ext2/ext3 file system

-F: Forced check

-P: Automatic repair

3. Mount: Associate a new file system to the current root file system

Uninstall: Pre-Remove a file system's association with the current root file system

When the mount is complete, the files on the corresponding file system are accessed via the mount point

Create a new directory under the/mnt/directory for the file system mount point (there will be a lost+found directory under the Mount directory)

Mount: Mount

Usage: Mount device mount point

Equipment:

Device file:/dev/sda5

Volume Label: label= ""

Uuid:uuid= ""

mount point: Directory

Requirements:

1. This directory is not used by other processes

2. The catalogue must exist beforehand

3, the original files in the directory will be temporarily hidden

Mount: Displays devices and mount points that are already mounted on the current system

mount [Options] [-o options] DEVICE mount_point

Command options Mount file system feature options

-A: Indicates that all file systems defined in the/etc/fstab file are mounted

-N: By default, the Mount command saves the mounted device information to the/etc/mtab file each time a device is mounted, and using the-N option means that the information is not written to the file when the device is mounted

-T Fstype: Specifies the type of file system on which the device is being mounted; When this option is not used, Mount invokes the Blkid command to obtain the type of the corresponding file system

-R: Read-only mount, Mount disc often with this option

-W: Read-write Mount

-O: Specify additional mount options, that is, specify the properties that the file system enables

Remount: Re-mount the current file system

RO: Mount as read-only

RW: Read-write Mount

Umount: Uninstalling a file system

Umount Equipment

Umount mount point

Uninstall considerations:

The mounted device is not in process use (not in a directory that needs to be mounted)

Practice:

1, create a 2G partition, the file system is ext2, the volume is labeled data, the block size is 1024, the reserved management space for the disk partition of 8%, mounted to the/backup directory, requires the use of the volume label to mount, and on the mount to start the ACL function on this file system

# mke2fs-l Data-b 1024-m 8/dev/sda7

# mount-o ACL Label=data/backup

# Tune2fs-o ACL/DEV/SDA7

# Mount Label=data/backup

2. Save the block and Inode rows from the information in the super block of this file system to/tmp/partition.txt

# Tune2fs-l | Egrep-i "Block|inode" >>/tmp/partition.txt

3, copy all the files in/etc directory to this file system, and then adjust this file system type is ext3, the request cannot damage the files that have been copied

# cp-r/etc/*/backup

# tune2-j/dev/sda7

4. Adjust its reserved percentage to 3%

# tune2fs-m 3-l Data/dev/sda7

5. Mount this file system in a re-mount mode to not update the access timestamp and verify its effect

# Stat/backup/inittab

# Cat/backup/inittab

# Stat

# Mount-o Remount,noatime/backup

# Cat

# Stat

6, the file system forced to do a test

# e2fsck-f/DEV/SDA7

7, delete all the copied files and re-mount the file system as sync (sync), and then copy all the files in the/etc directory to this mount point to experience its performance changes

# rm-rf/backup/*

# Mount-o Remount,sync/backup

# cp-r/etc/*/backup

This article is from "Luo Chen's blog" blog, please be sure to keep this source http://luochen2015.blog.51cto.com/9772274/1641812

Disk and File System Management (II)