How to use Linux Disk Management, file system and related commands

Linux Disk Management

Hard disk:

Mechanical HDD

SSD solid-State drives

Track

Sector:512bytes

Cylinder: The basic unit of the partition;

MBR : Master Boot Record

512bytes 446:bootloader 64:filesystem allocation table: identifies a partition 2:55AA

Disk interface type:

IDE (ATA) : 133mb/s,/dev/hd

scsi:640mb/s

SATA : 6Gbps

SAS : 6Gbps

USB : 480mb/s

Identify the hard drive device:/DEV/SD

Mark a different hard drive device:/dev/sd[a-z]

Mark different partitions on the same device:/dev/sd[a-z][1-]

1-4: primary or extended partition identification

5+ : Logical partition Identification

Device Files: Special files

Device number: Major, minor

Major: Device Type

Minor: different devices under the same type

" blocks ": block, Random device

" character ": Character, linear device

Partitioning: Separates the storage space into multiple small spaces, each of which can use the file system independently;

Partitioning tools: fdisk, parted, Sfdisk

fdisk tool Usage: Supports up to 15 partitions on one hard drive;

Partition Management sub-command:

P: Show

N: Create

D: Delete

T: Modify partition ID

L: list all support ID types

W: Save Exit

Q: Discard changes and exit

m: Get help

After the creation is complete, check to see if the kernel has identified the new partition:

# cat/proc/partitions

There are three commands that allow the kernel to reread the disk partition table:

CentOS 5:partprobe [DEVICE]

CentOS 6 or 7:partx,kpartx

Partx command:

Partx DEVICE

Partx-a DEVICE

Partx-a-N m:n DEVICE

M

M:

: N

Kpartx command:

Kpartx-af DEVICE

Linux File System Management

File system:

VFS : Virtual File System

Linux : Ext2, Ext3, Ext4, ReiserFS, Xfs,btrfs, swap

Disc: iso9660

Windows:fat32 (VFAT), NTFS

Unix:ffs, UFS, JFS, JFS2

Network File System: NFS, CIFS

Cluster file system: OCFS2, GFS2

Distributed File systems: Ceph, Moosefs, MogileFS, HDFs, GFS, Glusterfs

(1) journaled file System

Non-journaled file system: ext2

journaled File System: ext3

(2) Swap: Swap partition

To create a file system:

Perform formatting on a partition (advanced formatting)

To use a file system, two conditions are met:

Kernel: Support for this file system

User space: There are file System management tools

Create tool: Mkfs (make filesystem)

MKFS Usage:

MKFS-T type DEVICE

Mkfs.type DEVICE

ext dedicated management tools for series file systems:

mke2fs-t {EXT2|EXT3|EXT4} DEVICE

-B block:1024, 2048, 4096

- l ' LABEL ': set the volume label

Blkid command:

Blkid DEVICE

LABEL, UUID, TYPE

Homework:

1. allow ordinary users to use/tmp/cat to view/etc/shadow files;

[Email protected] ~]# cp/usr/bin/cat/tmp/

[Email protected] ~]# cd/tmp/

[Email protected] tmp]# chmod u+s Cat

[email protected] tmp]# su tgy

[Email protected] tmp]$/tmp/cat/etc/shadow

2. Create a directory/test/data, let a group of ordinary users have write permissions to it, and all the files created by the group is the directory belongs to the group, in addition, each user can only delete their own files;

[Email protected]/]# mkdir-p/test/data

[Email protected]/]# chmod g+w/test/data/

[Email protected]/]# chmod g+s/test/data/

[Email protected]/]# chmod o+t/test/data/

How to use Linux Disk Management, file system and related commands