给linux系统添加新的磁盘

虚拟化环境中，我们经常会遇到需要增加磁盘容量的情况，通常有两种方式，第一种是添加一块新的硬盘，另一种是扩容原有磁盘，以下是添加新磁盘至linux系统的操作规范。注：具体磁盘信息可能有所不同。

##查看新增加磁盘/dev/sdb的信息

[root@CentOS7 ~]# fdisk -l /dev/sdb

Disk /dev/sdb: 5368 MB, 5368709120 bytes, 10485760 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

##在新磁盘/dev/sdb上创建分区

[root@CentOS7 ~]# fdisk /dev/sdb

Welcome to fdisk (util-linux 2.23.2).

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

Building a new DOS disklabel with disk identifier 0x8c60b336.

Command (m for help): n   ##新建分区

Partition type:

   p   primary (0 primary, 0 extended, 4 free)

   e   extended

Select (default p): p ##主分区

Partition number (1-4, default 1):             ##保持默认

First sector (2048-10485759, default 2048):      ##保持默认

Last sector, +sectors or +size{K,M,G} (2048-10485759, default 10485759): +100M        ##磁盘分区大小为100MB

Partition 1 of type Linux and of size 100 MiB is set

Command (m for help): w  ##写入分区信息

The partition table has been altered!

Using default value 2048

Calling ioctl() to re-read partition table.

Syncing disks.

[root@CentOS7 ~]# fdisk -l /dev/sdb     ##再次查看/dev/sdb的信息，此时应该有新增的一个分区/dev/sdb1

Disk /dev/sdb: 5368 MB, 5368709120 bytes, 10485760 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

Disk label type: dos

Disk identifier: 0x8c60b336

   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1            2048      206847      102400   83  Linux

[root@CentOS7 ~]# blkid /dev/sdb1      ##查看分区信息，因为此时并没有格式化，所以此处无任何显示

[root@CentOS7 ~]# mkfs -t ext4 /dev/sdb1     ##格式化分区/dev/sdb1，格式为ext4

mke2fs 1.42.9 (28-Dec-2013)

Filesystem label=

OS type: Linux

Block size=1024 (log=0)

Fragment size=1024 (log=0)

Stride=0 blocks, Stripe width=0 blocks

25688 inodes, 102400 blocks

5120 blocks (5.00%) reserved for the super user

First data block=1

Maximum filesystem blocks=33685504

13 block groups

8192 blocks per group, 8192 fragments per group

1976 inodes per group

Superblock backups stored on blocks:

            8193, 24577, 40961, 57345, 73729

Allocating group tables: done                           

Writing inode tables: done                           

Creating journal (4096 blocks): done

Writing superblocks and filesystem accounting information: done

[root@CentOS7 ~]# blkid /dev/sdb1      ##再次查看分区信息，此时已经有磁盘ID和分区类型

/dev/sdb1: UUID="a7a1bc0d-eddd-46e8-8b06-27b41b287424" TYPE="ext4"

[root@CentOS7 ~]# mkdir /Data             ##创建新的数据挂载点

[root@CentOS7 ~]# mount /dev/sdb1 /Data/  ##挂载新分区/dev/sdb1至新的挂载点

[root@CentOS7 ~]# mount          ##查看现在系统的挂载信息

sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime,seclabel)

……

/dev/sdb1 on /Data type ext4 (rw,relatime,seclabel,data=ordered)            ##已经成功挂载