Linux_磁盘分区

一、磁盘分区：

1、分区之前,需要先给虚拟机添加一块磁盘，以便于我们做后续的实验vmware虚拟机，请按如下进行操作

• 1.找到对应虚拟主机点击右键,选择设置
• 2.在硬件向导里面点击添加按钮，在硬件类型中选中“硬盘”，点击下一步
• 3.磁盘类型选择默认，然后创建新虚拟磁盘,调整大小(不要勾选立即分配空间)
• 4.最后点击下一步，完成即可

2、分区工具有fdisk和gdisk，当硬盘小于2T的时候我们应该用fdisk来分区，而当硬盘大于2T的时候则应用gdisk来进行分区

二、使用fidsk创建分区

1、fdisk命令

• fdisk常用选项：
  • -l 列出素所有分区表
  • -u 与"-l"搭配使用，显示分区数目

2、fdisk菜单操作说明：

Command (m for help): m //输入m列出常用的命令
Command action
a     toggle a bootable flag                //切换分区启动标记
b     edit bsd disklabel                    //编辑sdb磁盘标签
c     toggle the dos compatibility flag     //切换dos兼容模式
d     delete a partition                    //删除分区
l     list known partition types            //显示分区类型
m     print this menu                       //显示帮助菜单
n     add a new partition                   //新建分区
o     create a new empty DOS partition table       //创建新的空白分区表
p     print the partition table                    //显示分区表的信息
q     quit without saving changes                  //不保存退出
s     create a new empty Sun disklabel 7           //创建新的Sun磁盘标签
t     change a partition's system id               //修改分区ID,可以通过1查看id
u     change disp lay/entry units                  //修改容量单位,磁柱或扇区
V     verify the partition table                   //检验分区表
w     write table to disk and exit                 //保存退出
x     extra functionality (experts only)           //拓展功能

3、实例：

• 使用fdisk创建一个主分区（+5G）

[root@localhost ~]# fdisk /dev/nvme0n2
Welcome to fdisk (util-linux 2.32.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
 
Device does not contain a recognized partition table.
Created a new DOS disklabel with disk identifier 0xc3bdb27b.
 
Command (m for help): n       //新建分区
Partition type
   p   primary (0 primary, 0 extended, 4 free)
   e   extended (container for logical partitions)
Select (default p): p        //新建一个主分区
Partition number (1-4, default 1): 1         //分区编号，默认是1
First sector (2048-104857599, default 2048):          //起始大小，默认大小是2048M
Last sector, +sectors or +size{K,M,G,T,P} (2048-104857599, default 104857599): +5G  //该分区的大小是5G
 
Created a new partition 1 of type 'Linux' and of size 5 GiB.
 
Command (m for help): p          //列出分区信息
Disk /dev/nvme0n2: 50 GiB, 53687091200 bytes, 104857600 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xc3bdb27b
 
Device         Boot Start      End  Sectors Size Id Type
/dev/nvme0n2p1       2048 10487807 10485760   5G 83 Linux
 
Command (m for help): w         //保存退出
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
 
 //加载分区信息
[root@localhost ~]# partprobe
Warning: Unable to open /dev/sr0 read-write (Read-only file system).  /dev/sr0 has been opened read-only.
 
//查看分区信息
[root@localhost ~]# lsblk
NAME          MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sr0            11:0    1  7.3G  0 rom  /mnt
nvme0n1       259:0    0  120G  0 disk
├─nvme0n1p1   259:1    0    1G  0 part /boot
└─nvme0n1p2   259:2    0  119G  0 part
  ├─rhel-root 253:0    0   50G  0 lvm  /
  ├─rhel-swap 253:1    0    2G  0 lvm  [SWAP]
  └─rhel-home 253:2    0   67G  0 lvm  /home
nvme0n2       259:3    0   50G  0 disk
└─nvme0n2p1   259:5    0    5G  0 part

• 使用fdisk创建一个扩展分区（剩余空间全部）

[root@localhost ~]# fdisk /dev/nvme0n2
 
Welcome to fdisk (util-linux 2.32.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
 
 
Command (m for help): n       //新建一个分区
Partition type
   p   primary (1 primary, 0 extended, 3 free)
   e   extended (container for logical partitions)
Select (default p): e         //新建一个额外的分区（扩展分区）
Partition number (2-4, default 2): 2           //分区编号，默认是2     
First sector (10487808-104857599, default 10487808):              //该分区起始大小
Last sector, +sectors or +size{K,M,G,T,P} (10487808-104857599, default 104857599):     //结束大小；扩展分区分配剩余所有的空间大小
    
Created a new partition 2 of type 'Extended' and of size 45 GiB.
 
Command (m for help): p           //列出分区信息
Disk /dev/nvme0n2: 50 GiB, 53687091200 bytes, 104857600 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x8f03f9d8
 
Device         Boot    Start       End  Sectors Size Id Type
/dev/nvme0n2p1          2048  10487807 10485760   5G 83 Linux
/dev/nvme0n2p2      10487808 104857599 94369792  45G  5 Extended
 
Command (m for help): w          //保存退出
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
 
[root@localhost ~]# partprobe
Warning: Unable to open /dev/sr0 read-write (Read-only file system).  /dev/sr0 has been opened read-only.

//查看分区信息
[root@localhost ~]# lsblk
NAME          MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sr0            11:0    1  7.3G  0 rom  /mnt
nvme0n1       259:0    0  120G  0 disk
├─nvme0n1p1   259:1    0    1G  0 part /boot
└─nvme0n1p2   259:2    0  119G  0 part
  ├─rhel-root 253:0    0   50G  0 lvm  /
  ├─rhel-swap 253:1    0    2G  0 lvm  [SWAP]
  └─rhel-home 253:2    0   67G  0 lvm  /home
nvme0n2       259:3    0   50G  0 disk
├─nvme0n2p1   259:4    0    5G  0 part
└─nvme0n2p2   259:5    0    1K  0 part 　　

• 使用fdisk在扩展分区里面创建逻辑分区（+10G）

[root@localhost ~]# fdisk /dev/nvme0n2
 
Welcome to fdisk (util-linux 2.32.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
 
 
Command (m for help): n     //新建一个分区
All space for primary partitions is in use.
Adding logical partition 5        //默认的第一个逻辑分区编号是从5开始
First sector (10489856-104857599, default 10489856):     //该分区的起始大小
Last sector, +sectors or +size{K,M,G,T,P} (10489856-104857599, default 104857599): +10G      //分区结束大小10G  
 
Created a new partition 5 of type 'Linux' and of size 10 GiB.
 
Command (m for help): p         //查看分区列表信息
Disk /dev/nvme0n2: 50 GiB, 53687091200 bytes, 104857600 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x8f03f9d8
 
Device         Boot    Start       End  Sectors Size Id Type
/dev/nvme0n2p1          2048  10487807 10485760   5G 83 Linux
/dev/nvme0n2p2      10487808 104857599 94369792  45G  5 Extended
/dev/nvme0n2p5      10489856  31461375 20971520  10G 83 Linux
 
Command (m for help): w          //保存退出
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
 
//重新读取分区表
[root@localhost ~]# partprobe
Warning: Unable to open /dev/sr0 read-write (Read-only file system).  /dev/sr0 has been opened read-only.

//查看分区信息
[root@localhost ~]# lsblk
NAME          MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sr0            11:0    1  7.3G  0 rom  /mnt
nvme0n1       259:0    0  120G  0 disk
├─nvme0n1p1   259:1    0    1G  0 part /boot
└─nvme0n1p2   259:2    0  119G  0 part
  ├─rhel-root 253:0    0   50G  0 lvm  /
  ├─rhel-swap 253:1    0    2G  0 lvm  [SWAP]
  └─rhel-home 253:2    0   67G  0 lvm  /home
nvme0n2       259:3    0   50G  0 disk
├─nvme0n2p1   259:7    0    5G  0 part
├─nvme0n2p2   259:8    0    1K  0 part
└─nvme0n2p5   259:9    0   10G  0 part

 三、磁盘分区格式化

1、使用mkfs（make filesystem）命令格式化磁盘，创建文件系统:

• mkfs（make filesystem）常用的选项有：
  
  • -b          //设定数据区块占用空间大小， 目前支持1024、2048、4096 bytes每个块大小
  • -t           //用来指定什么类型的文件系统，可以是ext3，ext4， xfs
  • -i           //设定inode的大小
  • -N         //设定inode数量，防止Inode 数量不够导致磁盘不足
  • -L          //'LABEL': 设定卷标

• mkfs示例：

  • mkfs.ext4 /dev/DEVICENAME
  • mkfs -t ext4 /dev/DEVICENAME

• mke2fs：ext系列文件系统专用管理工具：

  • -t {ext2|ext3|ext4}
  • -b {1024|2048|4096}
  • -L 'LABEL'：设定卷标
  • -j: 相当于 -t ext3

2、格式化文件系统类型：

• 当前系统支持的文件系统：cat /etc/filesystems
• Linux文件系统: ext2, ext3, ext4, xfs, swap, iso9660
  • ext4: 默认文件系统
  • swap: 交换分区，相当于虚拟内存（当内存耗尽前才会使用）
  • 光盘：iso9660
• Windows：FAT32, NTFS
• Unix: FFS, UFS, JFS2
• 网络文件系统：NFS, CIFS

3、使用blkid查看格式化后设备的属性信息

• blkid：块设备属性信息查看
  • blkid [OPTION]... [DEVICE]
    
    • -U UUID: 根据指定的UUID来查找对应的设备
    • -L LABEL：根据指定的LABEL来查找对应的设备
• e2label：管理ext系列文件系统的LABEL
  • e2label DEVICE [LABEL]

4、使用mkfs格式化主分区：

 //查看以及创建的主分区
[root@localhost ~]# lsblk 
NAME          MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sr0            11:0    1  7.3G  0 rom  /mnt
nvme0n1       259:0    0  120G  0 disk 
├─nvme0n1p1   259:1    0    1G  0 part /boot
└─nvme0n1p2   259:2    0  119G  0 part 
  ├─rhel-root 253:0    0   50G  0 lvm  /
  ├─rhel-swap 253:1    0    2G  0 lvm  [SWAP]
  └─rhel-home 253:2    0   67G  0 lvm  /home
nvme0n2       259:3    0   50G  0 disk 
└─nvme0n2p1   259:4    0    5G  0 part 

//以文件名格式化主分区
[root@localhost ~]# mkfs.ext4 /dev/nvme0n2p1 
mke2fs 1.44.6 (5-Mar-2019)
Creating filesystem with 1310720 4k blocks and 327680 inodes
Filesystem UUID: 47dcacad-d395-4cdf-806a-28f7cd126a2b
Superblock backups stored on blocks: 
	32768, 98304, 163840, 229376, 294912, 819200, 884736

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (16384 blocks): done
Writing superblocks and filesystem accounting information: done 

//查看已经格式化的主分区的属性
[root@localhost ~]# blkid /dev/nvme0n2p1 
/dev/nvme0n2p1: UUID="47dcacad-d395-4cdf-806a-28f7cd126a2b" TYPE="ext4" PARTUUID="8f03f9d8-01"

• 使用mkfs -t格式化主分区

 //查看分区信息
[root@localhost ~]# lsblk 
NAME          MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sr0            11:0    1  7.3G  0 rom  /mnt
nvme0n1       259:0    0  120G  0 disk 
├─nvme0n1p1   259:1    0    1G  0 part /boot
└─nvme0n1p2   259:2    0  119G  0 part 
  ├─rhel-root 253:0    0   50G  0 lvm  /
  ├─rhel-swap 253:1    0    2G  0 lvm  [SWAP]
  └─rhel-home 253:2    0   67G  0 lvm  /home
nvme0n2       259:3    0   50G  0 disk 
└─nvme0n2p1   259:5    0    5G  0 part 

//格式化主分区
[root@localhost ~]# mkfs -t ext4 /dev/nvme0n2p1 
mke2fs 1.44.6 (5-Mar-2019)
Creating filesystem with 1310720 4k blocks and 327680 inodes
Filesystem UUID: a9622acc-4419-4416-9d16-ed7fa1a2b476
Superblock backups stored on blocks: 
	32768, 98304, 163840, 229376, 294912, 819200, 884736

Allocating group tables: done                            
Writing inode tables: done                            
Creating journal (16384 blocks): done
Writing superblocks and filesystem accounting information: done 

//查看格式化后主分区的属性
[root@localhost ~]# blkid /dev/nvme0n2p1 
/dev/nvme0n2p1: UUID="a9622acc-4419-4416-9d16-ed7fa1a2b476" TYPE="ext4" PARTUUID="8f03f9d8-01"