安装Linux的第一步就是创建磁盘系统,而创建系统主要分为成两个步骤:
1. 创建分区,2.创建文件系统
创建分区:
常用三个命令fdisk,parted
fdisk:是最常用的
限制:
1. fdisk不支持gpt磁盘, 也就是说它不能划分大于2T的分区 (例如下图)
2. 最多划分15个分区
# fdisk /dev/sdb Warning: invalid flag 0x0000 of partition table 4 willbe corrected by w(rite) WARNING: The size of this disk is 5.9 TB (5908688535552bytes). DOS partition table format can not be used on drivesfor volumes larger than (2199023255040 bytes) for 512-byte sectors.Use parted(1) and GUID partition table format (GPT).
如果需要划分大于2T的分区,需要用到命令parted下文会有介绍
我们通过下面的例子来划分个新的分区并且介绍一些常用参数
查看系统上说有可识别的磁盘, 通过grep命令来过滤所有磁盘信息.
[root@centos~]# fdisk -l | grep "Disk /dev/sd.*" Disk/dev/sda: 53.7 GB, 53687091200 bytes Disk/dev/sdb: 21.5 GB, 21474836480 bytes
2.选择要分区的硬盘
[root@centos ~]# fdisk /dev/sdb WARNING: DOS-compatible mode is deprecated. It'sstrongly recommended to switchoff the mode (command 'c') and change display units to sectors(command 'u'). Command (m for help):
3. 依次通过命令n(创建一个新的分区), 4(选择第几个分区), +500M(这个分区大小为500M),w(存储并且退出)
在输入w前可以用p命令查看结果,如果不满意可以直接q退出而不用保存.
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Selected partition 4
First cylinder (147-2610, default 147): 4
Value out of range.
First cylinder (147-2610, default 147):
Using default value 147
Last cylinder, +cylinders or +size{K,M,G} (147-2610,default 2610): +500M
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed witherror 16: Device or resource busy.
The kernel still uses the old table. The new table willbe used at
the next reboot or after you run partprobe(8) orkpartx(8)
Syncing disks.
parted命令
查看所有当前分区
[root@centos ~]# parted /dev/sdb GNU Parted 2.1 Using /dev/sdb Welcome to GNU Parted! Type 'help' to view a list ofcommands. (parted) print Model: VMware, VMware Virtual S (scsi) Disk /dev/sdb: 21.5GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 32.3kB 115MB 115MB primary ext4 2 115MB 658MB 543MB primary ext4 3 658MB 1201MB 543MB primary ext3 4 1201MB 1736MB 535MB primary
改变显示单位为TB
(parted) unit TB
格式化的时候一定要先上一步print出来,这样就知道从哪里开始格式化.
(parted) mkpartfs WARNING: you are attempting to use parted to operate on(mkpartfs) a file system. parted's file system manipulation code is not as robustas what you'll find in dedicated, file-system-specific packages likee2fsprogs. We recommend you use parted only to manipulate partition tables,whenever possible. Support for performing most operations on most types offile systems will be removed in an upcoming release. Partition type? primary/extended? primary File system type? [ext2]? Start? 17367 End? 18367 Warning: WARNING: the kernel failed to re-read thepartition table on /dev/sdb (Device or resource busy). As aresult, it may not reflect all of your changes until after reboot.
创建文件系统,
我们可以用–t ext2 ext3 来选择格式化成不同的文件类型
[root@centos ~]# mke2fs -t ext4 /dev/sdb3