Linux下使用fdisk扩大分区容量（不丢失数据）-IDC资讯中心

环境：

模拟新加一块磁盘，并分区，挂载，永久挂载，然后写入数据，然后对分区扩容，测试扩容后分区里面的内容是否丢失。

查看所有分区：

[root@backup
~]# fdisk
-l
Disk
/dev/sda: 1073.7 GB, 1073741824000 bytes

255 heads, 63 sectors/track, 130541
cylinders
Units
= cylinders of 16065 * 512 = 8225280 bytes
Sector
size (logical/physical): 512 bytes / 512 bytes
I/O
size (minimum/optimal): 512 bytes / 512 bytes
Disk
identifier: 0x00040b96

Device Boot Start End Blocks Id System
/dev/sda1
* 1 26 204800 83 Linux
Partition
1 does not end on cylinder boundary.
/dev/sda2
26 1070 8388608 82 Linux swap / Solaris
/dev/sda3
1070 13055 96263168 83 Linux
Disk
/dev/sdb: 1073.7 GB, 1073741824000 bytes
255
heads, 63 sectors/track, 130541 cylinders
Units
= cylinders of 16065 * 512 = 8225280 bytes
Sector
size (logical/physical): 512 bytes / 512 bytes
I/O
size (minimum/optimal): 512 bytes / 512 bytes
Disk
identifier: 0x00000000

开始分区：

[root@backup
~]# fdisk
/dev/sdb
Device
contains neither a valid DOS partition table, nor Sun, SGI or OSF
disklabel

Building a new DOS disklabel with disk identifier 0xc6e44e94.
Changes
will remain in memory only, until you decide to write them.
After
that, of course, the previous content won't be recoverable.

Warning:
invalid flag 0x0000 of partition table 4 will be corrected by w(rite)

WARNING:
DOS-compatible mode is deprecated. It's strongly recommended to

switch off the mode (command 'c') and change display units to

sectors (command 'u').

Command
(m for help): p
#p是打印当前磁盘所有分区Disk /dev/sdb: 1073.7 GB, 1073741824000 bytes
255
heads, 63 sectors/track, 130541 cylinders
Units
= cylinders of 16065 * 512 = 8225280 bytes
Sector
size (logical/physical): 512 bytes / 512 bytes
I/O
size (minimum/optimal): 512 bytes / 512 bytes
Disk
identifier: 0xc6e44e94

Device Boot Start End Blocks Id System

Command
(m for help): n
#n是新建分区Command action

e extended

p primary partition (1-4)p
#新建主分区
Partition
number (1-4): 1
#给主分区编号为1，从1开始编号
First
cylinder (1-130541, default 1): #回车，默认从1开始，也可以手动输入1
Using
default value 1
#起始分区的位置Last cylinder, +cylinders or +size{K,M,G}
(1-130541, default 130541):
#直接回车，默认把磁盘所有空间分配到此分区。这里支持K，M，G，如果想给此分区分配100M空间，就输入+100M;如果要分配100G那么就输入+100GUsing
default value 130541 #结束分区的位置
Command
(m for help): w
#w为写入分区信息并保存，然后退出The partition table has been altered!Calling
ioctl() to re-read partition table.

Syncing disks.

查看刚刚分区的信息：/dev/sdb1

[root@backup
~]# fdisk
-l
Disk
/dev/sda: 1073.7 GB, 1073741824000 bytes

格式化分区：mkfs.ext4 /dev/sdb1

[root@backup
~]# mkfs.ext4
/dev/sdb1
mke2fs
1.41.12 (17-May-2010)
Filesystem
label=
OS
type: Linux

Block
size=4096 (log=2)
Fragment
size=4096 (log=2)Stride=0 blocks,
Stripe
width=0 blocks

65536000 inodes, 262142637 blocks
13107131
blocks (5.00%) reserved for the super user
First
data block=0
Maximum
filesystem blocks=4294967296
8000
block groups32768 blocks per group, 32768 fragments per group
8192
inodes per group
Superblock
backups stored on blocks:

32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,

4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,

102400000, 214990848
Writing
inode tables: done Creating journal (32768 blocks):
doneWriting superblocks and filesystem accounting information:
doneThis
filesystem will be automatically checked every 26 mounts or
180
days, whichever comes first. Use tune2fs -c or -i to
override.

挂载分区：

[root@backup
backup]# mkdir
/backup
[root@backup
backup]# mount
/dev/sdb1 /backup/
[root@backup
backup]# df
-hT
Filesystem
Type Size Used Avail Use% Mounted on

/dev/sda3 ext4 91G 2.2G
84G 3% /
tmpfs
tmpfs 1.9G 0 1.9G 0% /dev/shm
/dev/sda1
ext4 190M 38M 142M 21% /boot
/dev/sdb1
ext4 985G 72M 935G 1% /backup

挂载磁盘：(永久挂载)

通过vi编辑器编辑/etc/fstab文件，内容如下，(最后一行是刚添加上去的)：

[root@backup
~]# cat
/etc/fstab
#

#
/etc/fstab

#
Created by anaconda on Mon May 14 02:01:11 2018

#
Accessible filesystems, by reference, are maintained under '/dev/disk'

#
See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info

#UUID=7d223255-1b77-4f58-bd72-262928547fcf
/ ext4 defaults 1
1

UUID=284d6b31-8723-497b-bc7b-3c12ede23ee6 /boot ext4
defaults 1 2
UUID=5d36c1b3-df6e-480d-80ca-72befc66f5e9
swap swap defaults 0 0
tmpfs
/dev/shm tmpfs defaults 0 0
devpts
/dev/pts devpts gid=5,mode=620 0 0
sysfs
/sys sysfs defaults 0 0
proc
/proc proc defaults 0 0
/dev/sdb1
/backup ext4 defaults 0
0

第四列挂载参数：通过查看man mount 来查看

第五列是否要备份：(0为不备份，1为要备份，一般情况下不用做备份)

第六列自检程序 (0为不自检，1或2为要自检，如果是根分区要设置1，其它分区只能是2)

[root@backup
~]# echo
backup >/backup/backup.txt
[root@backup
~]# cat
/backup/backup.txt
backup

此时机器不关机，用vmware vspere client扩容磁盘大小。

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

Disk
/dev/sdb: 1073.7 GB, 1073741824000 bytes

此时发现扩容的磁盘容量看不到，所以还是重启一下吧，建议关机时候再扩容。

[root@backup
~]# umount
/dev/sdb1 #取消挂载

[root@backup
~]# fdisk
/dev/sdb WARNING: DOS-compatible mode is deprecated. It's
strongly recommended to

switch off the mode (command 'c') and change
display units to

sectors (command 'u').
Command
(m for help): p
Disk
/dev/sdb: 1181.1 GB, 1181116006400 bytes
255
heads, 63 sectors/track, 143595 cylinders
Units
= cylinders of 16065 * 512 = 8225280 bytes
Sector
size (logical/physical): 512 bytes / 512 bytes
I/O
size (minimum/optimal): 512 bytes / 512 bytes
Disk
identifier: 0xc6e44e94

Device Boot Start End Blocks Id System
/dev/sdb1
1 130541 1048570551 83 Linux
Command
(m for help): d
#因为此磁盘只有一个分区sdb1，所以按d删除时候默认不会让选择要删除的分区，如果有多个分区会提示要删除的分区。Selected partition
1
Command
(m for help): p
#打印当前分区，发现分区已删除Disk /dev/sdb: 1181.1 GB, 1181116006400 bytes
255
heads, 63 sectors/track, 143595 cylinders
Units
= cylinders of 16065 * 512 = 8225280 bytes
Sector
size (logical/physical): 512 bytes / 512 bytes
I/O
size (minimum/optimal): 512 bytes / 512 bytes
Disk
identifier: 0xc6e44e94

Device Boot Start End Blocks Id System
Command
(m for help): n
#新建分区Command action

e extended

p primary partition (1-4)p
#新建主分区

Partition
number (1-4): 1
#和扩容前的分区标号必须一样

First
cylinder (1-143595, default 1):
#默认是1，比如要和扩容前的分区其实点一样，扩容前的分区起始也是1，这个是扩容的重点地方。

Using
default value 1

Last cylinder, +cylinders or +size{K,M,G} (1-143595, default
143595): #终止的位置是默认是硬盘柱体的尾部，即使最大值，这个是要扩容的点，回车。Using default value 143595

Command
(m for help): w
#w报错，并退出。

The
partition table has been altered!Calling ioctl() to re-read partition
table.

Syncing disks.

3、调整分区

e2fsck -f /dev/sdb1 #检查分区信息

resize2fs /dev/sdb1 #调整分区大小

[root@backup
~]# e2fsck
-f /dev/sdb1 #由于磁盘容量很大，数据多的情况下需要等待一段时间

e2fsck
1.41.12 (17-May-2010)Pass 1: Checking inodes, blocks, and sizes

Pass 2:
Checking directory structure
Pass
3: Checking directory connectivity
Pass
4: Checking reference counts
Pass
5: Checking group summary information

/dev/sdb1:
12/65536000 files (0.0% non-contiguous), 4164250/262142637 blocks

[root@backup
~]# resize2fs
/dev/sdb1 #由于磁盘容量很大，数据多的情况下需要等待一段时间

resize2fs
1.41.12 (17-May-2010)Resizing the filesystem on /dev/sdb1 to 288356701 (4k)
blocks.

The
filesystem on /dev/sdb1 is now 288356701 blocks long.

[root@backup
~]# mount
/dev/sdb1 /backup/

[root@backup
~]# cat
/backup/backup.txt lost+found/

[root@backup ~]# cat
/backup/backup.txt backup

发现扩容成功，扩容前的内容没有丢失。

Linux下使用fdisk扩大分区容量（不丢失数据）

相关推荐

热门标签

热门文章

分类目录