Linux系统下对硬盘分区进行扩容的方法总结

时间:2022-02-15 15:48:20

硬盘快满了,加硬盘扩容,不管是独立的服务器,还是云空间新买的硬盘,扩容方式一样。下面以阿里VPS为例,详细说一下,挂载硬盘扩容的2种方法。
阿里VPS,个人觉得有以下二个方面需要改进
1,默认不是lvm,所以系统盘/dev/xvda1是不能扩容的,所以如果有大数据的东西,一开始就要考虑到扩容的问题。数据量越大,操作风险越大。
2,不能实现无缝扩容,也就是说,在后台扩容一下,不用登录到VPS,进行调整。非专业人士,扩容困难

一,不采用lvm,直接将硬盘挂载到目录
1,查看硬盘分区情况

 

复制代码
代码如下:

[root@iZ94zz3wqciZ ~]# df 
Filesystem 1K-blocks Used Available Use% Mounted on 
/dev/xvda1 20641404 14778400 4814480 76% / 
tmpfs 509300 0 509300 0% /dev/shm 

[root@iZ94zz3wqciZ ~]# fdisk -l 

Disk /dev/xvda: 21.5 GB, 21474836480 bytes 
255 heads, 63 sectors/track, 2610 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: 0x00078f9c 

Device Boot Start End Blocks Id System 
/dev/xvda1 * 1 2611 20970496 83 Linux //id是83,非lvm 

Disk /dev/xvdb: 23.6 GB, 23622320128 bytes //新买的硬盘 
255 heads, 56 sectors/track, 3230 cylinders 
Units = cylinders of 14280 * 512 = 7311360 bytes 
Sector size (logical/physical): 512 bytes / 512 bytes 
I/O size (minimum/optimal): 512 bytes / 512 bytes 
Disk identifier: 0x27cc1f5a 

 

2,硬盘分区并查看分区情况
 

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代码如下:

[root@iZ94zz3wqciZ ~]# fdisk -S 56 /dev/xvdb //分区 

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): n //输入n 
Command action 
e extended 
p primary partition (1-4) 
p //主分区 
Partition number (1-4): 1 //分区号1 
First cylinder (1-3230, default 1): 
Using default value 1 
Last cylinder, +cylinders or +size{K,M,G} (1-3230, default 3230): 
Using default value 3230 

Command (m for help): wq //保存并退出 
The partition table has been altered! 

[root@iZ94zz3wqciZ ~]# fdisk -l 

Disk /dev/xvda: 21.5 GB, 21474836480 bytes 
255 heads, 63 sectors/track, 2610 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: 0x00078f9c 

Device Boot Start End Blocks Id System 
/dev/xvda1 * 1 2611 20970496 83 Linux 

Disk /dev/xvdb: 23.6 GB, 23622320128 bytes 
255 heads, 56 sectors/track, 3230 cylinders 
Units = cylinders of 14280 * 512 = 7311360 bytes 
Sector size (logical/physical): 512 bytes / 512 bytes 
I/O size (minimum/optimal): 512 bytes / 512 bytes 
Disk identifier: 0x27cc1f5a 

Device Boot Start End Blocks Id System 
/dev/xvdb1 1 3230 23062172 83 Linux //分区后 

 

3,格式化新分区xvdb1
 

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代码如下:

[root@iZ94zz3wqciZ ~]# mkfs.ext4 /dev/xvdb1 //格式化分区 
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 
1441792 inodes, 5765543 blocks 
288277 blocks (5.00%) reserved for the super user 
First data block=0 
Maximum filesystem blocks=4294967296 
176 block groups 
32768 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 

Writing inode tables: done 
Creating journal (32768 blocks): done 
Writing superblocks and filesystem accounting information: done 

This filesystem will be automatically checked every 35 mounts or 
180 days, whichever comes first. Use tune2fs -c or -i to override. 

 

4,创建目录,并挂载分区
 

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代码如下:

[root@iZ94zz3wqciZ ~]# mkdir /mnt/fastdfs //挂载目录 
[root@iZ94zz3wqciZ ~]# echo "/dev/xvdb1 /mnt/fastdfs ext4 defaults 0 0" >> /etc/fstab //重启会自动挂载 
[root@iZ94zz3wqciZ ~]# mount -a //挂载所有目录 

[root@iZ94zz3wqciZ ~]# df 
Filesystem 1K-blocks Used Available Use% Mounted on 
/dev/xvda1 20641404 14778404 4814476 76% / 
tmpfs 509300 0 509300 0% /dev/shm 
/dev/xvdb1 22694396 176064 21365516 1% /mnt/fastdfs //新的分区已挂载 

到这儿,就把一块独立的硬盘加到系统当中了。这种扩容的方式操作简单,但是扩展性不强,不推荐这种扩容方式。

 

二,采用lvm的方式,进行硬盘扩容(推荐)
1,取消前面测试的挂载,并删除分区

 

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代码如下:

[root@iZ94zz3wqciZ ~]# umount -a //取消挂载 

[root@iZ94zz3wqciZ ~]# fdisk /dev/xvdb //分区 

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): d //删除分区 
Selected partition 1 

Command (m for help): wq //保存 
The partition table has been altered! 

2,安装lvm

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代码如下:

[root@iZ94zz3wqciZ nginx]# uname -a //查看内核信息 
Linux iZ94zz3wqciZ 2.6.32-431.23.3.el6.x86_64 #1 SMP Thu Jul 31 17:20:51 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux 

[root@iZ94zz3wqciZ ~]# yum install lvm2 device-mapper //安装 LVM2,2.6.9以后版本不用装device-mapper 

[root@iZ94zz3wqciZ nginx]# lsmod | grep dm_mod //是否加载了dm_mod 
dm_mod 84337 5 dm_mirror,dm_log 

lvm的安装,首先加载device-mapper模块,从linux内核2.6.9开始,device-mapper模块就已经包含在内,所以你只需加载即可。加载mapper模块:modprobe dm_mod。
3,创建lvm分区

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代码如下:

[root@iZ94zz3wqciZ ~]# fdisk /dev/xvdb //分区 

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): l 

0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris 
1 FAT12 39 Plan 9 82 Linux swap / So c1 DRDOS/sec (FAT- 
2 XENIX root 3c PartitionMagic 83 Linux c4 DRDOS/sec (FAT- 
3 XENIX usr 40 Venix 80286 84 OS/2 hidden C: c6 DRDOS/sec (FAT- 
4 FAT16 <32M 41 PPC PReP Boot 85 Linux extended c7 Syrinx 
5 Extended 42 SFS 86 NTFS volume set da Non-FS data 
6 FAT16 4d QNX4.x 87 NTFS volume set db CP/M / CTOS / . 
7 HPFS/NTFS 4e QNX4.x 2nd part 88 Linux plaintext de Dell Utility 
8 AIX 4f QNX4.x 3rd part 8e Linux LVM df BootIt 
9 AIX bootable 50 OnTrack DM 93 Amoeba e1 DOS access 
a OS/2 Boot Manag 51 OnTrack DM6 Aux 94 Amoeba BBT e3 DOS R/O 
b W95 FAT32 52 CP/M 9f BSD/OS e4 SpeedStor 
c W95 FAT32 (LBA) 53 OnTrack DM6 Aux a0 IBM Thinkpad hi eb BeOS fs 
e W95 FAT16 (LBA) 54 OnTrackDM6 a5 FreeBSD ee GPT 
f W95 Ext'd (LBA) 55 EZ-Drive a6 OpenBSD ef EFI (FAT-12/16/ 
10 OPUS 56 Golden Bow a7 NeXTSTEP f0 Linux/PA-RISC b 
11 Hidden FAT12 5c Priam Edisk a8 Darwin UFS f1 SpeedStor 
12 Compaq diagnost 61 SpeedStor a9 NetBSD f4 SpeedStor 
14 Hidden FAT16 <3 63 GNU HURD or Sys ab Darwin boot f2 DOS secondary 
16 Hidden FAT16 64 Novell Netware af HFS / HFS+ fb VMware VMFS 
17 Hidden HPFS/NTF 65 Novell Netware b7 BSDI fs fc VMware VMKCORE 
18 AST SmartSleep 70 DiskSecure Mult b8 BSDI swap fd Linux raid auto 
1b Hidden W95 FAT3 75 PC/IX bb Boot Wizard hid fe LANstep 
1c Hidden W95 FAT3 80 Old Minix be Solaris boot ff BBT 
1e Hidden W95 FAT1 

Command (m for help): n 
Command action 
e extended 
p primary partition (1-4) 

Partition number (1-4): 1 
First cylinder (1-2871, default 1): 
Using default value 1 
Last cylinder, +cylinders or +size{K,M,G} (1-2871, default 2871): 
Using default value 2871 

Command (m for help): p 

Disk /dev/xvdb: 23.6 GB, 23622320128 bytes 
255 heads, 63 sectors/track, 2871 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: 0x27cc1f5a 

Device Boot Start End Blocks Id System 
/dev/xvdb1 1 2871 23061276 83 Linux //不是lvm分区格式 

Command (m for help): t //转换 
Selected partition 1 
Hex code (type L to list codes): 8e //换成8e 
Changed system type of partition 1 to 8e (Linux LVM) 

Command (m for help): p 

Disk /dev/xvdb: 23.6 GB, 23622320128 bytes 
255 heads, 63 sectors/track, 2871 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: 0x27cc1f5a 

Device Boot Start End Blocks Id System 
/dev/xvdb1 1 2871 23061276 8e Linux LVM //现在lvm分区格式了 

Command (m for help): wq 
The partition table has been altered! 

Calling ioctl() to re-read partition table. 
Syncing disks. 

4,创建逻辑卷组,以及逻辑卷等

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代码如下:

[root@iZ94zz3wqciZ ~]# pvcreate /dev/xvdb1 //创建物理卷 
Physical volume "/dev/xvdb1" successfully created 

[root@iZ94zz3wqciZ ~]# vgcreate myfiles /dev/xvdb1 //创建逻辑卷组 
Volume group "myfiles" successfully created 

[root@iZ94zz3wqciZ ~]# vgchange -ay myfiles //激活逻辑卷组 
0 logical volume(s) in volume group "myfiles" now active 

[root@iZ94zz3wqciZ ~]# vgdisplay myfiles | grep "Total PE" //查看该卷组所有的PE 
Total PE 5629 

[root@iZ94zz3wqciZ ~]# lvcreate -l 5629 -n fastdfs myfiles //创建逻辑卷 
Logical volume "fastdfs" created.
  
5,格式化逻辑卷

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代码如下:

[root@iZ94zz3wqciZ ~]# mkfs.ext4 /dev/myfiles/fastdfs //格式化逻辑卷 
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 
1441792 inodes, 5764096 blocks 
288204 blocks (5.00%) reserved for the super user 
First data block=0 
Maximum filesystem blocks=4294967296 
176 block groups 
32768 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 

Writing inode tables: done 
Creating journal (32768 blocks): done 
Writing superblocks and filesystem accounting information: done 

This filesystem will be automatically checked every 39 mounts or 
180 days, whichever comes first. Use tune2fs -c or -i to override. 

6,设置自动挂载,并查看分区

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代码如下:

[root@iZ94zz3wqciZ ~]# echo '/dev/myfiles/fastdfs /mnt/fastdfs ext4 defaults 0 0' >> /etc/fstab //自动挂载 
[root@iZ94zz3wqciZ ~]# mount -a //手动挂载 
[root@iZ94zz3wqciZ ~]# df 
Filesystem 1K-blocks Used Available Use% Mounted on 
/dev/xvda1 20641404 14778608 4814272 76% / 
tmpfs 509300 0 509300 0% /dev/shm 
/dev/mapper/myfiles-fastdfs 
22694396 176064 21365516 1% /mnt/fastdfs //lvm逻辑卷已挂载 

[root@iZ94zz3wqciZ ~]# reboot //操作完最好重启一下 

7,再扩容一块硬盘到已有逻辑卷

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代码如下:

[root@iZ94zz3wqciZ ~]# fdisk /dev/xvdc //详细过程同上,就不详细说明了 

[root@iZ94zz3wqciZ ~]# reboot 

[root@iZ94zz3wqciZ ~]# pvcreate /dev/xvdc1 //创建物理卷 
Physical volume "/dev/xvdc1" successfully created 

[root@iZ94zz3wqciZ ~]# vgextend myfiles /dev/xvdc1 //将新硬盘加入卷组 
Volume group "myfiles" successfully extended 

[root@iZ94zz3wqciZ ~]# vgdisplay myfiles | grep "Total PE" //查看所有PE 
Total PE 6907 

[root@iZ94zz3wqciZ ~]# lvresize -l 6907 /dev/myfiles/fastdfs //重新规定大小 
Size of logical volume myfiles/fastdfs changed from 21.99 GiB (5629 extents) to 26.98 GiB (6907 extents). 
Logical volume fastdfs successfully resized 

[root@iZ94zz3wqciZ ~]# resize2fs /dev/myfiles/fastdfs //重新规定大小 
resize2fs 1.41.12 (17-May-2010) 
Filesystem at /dev/myfiles/fastdfs is mounted on /mnt/fastdfs; on-line resizing required 
old desc_blocks = 2, new_desc_blocks = 2 
Performing an on-line resize of /dev/myfiles/fastdfs to 7072768 (4k) blocks. 
The filesystem on /dev/myfiles/fastdfs is now 7072768 blocks long. 

[root@iZ94zz3wqciZ ~]# df -h 
Filesystem Size Used Avail Use% Mounted on 
/dev/xvda1 20G 15G 4.6G 76% / 
tmpfs 498M 0 498M 0% /dev/shm 
/dev/mapper/myfiles-fastdfs 
27G 172M 26G 1% /mnt/fastdfs //新的5G硬盘加上去了 

如果是频繁的扩容硬盘的话,LVM是首选,扩展真的很方便。