本文介绍 CentOS 7.x 系统创建 LVM 系统分区的命令与方法。
目录
- 版本说明
- 方法步骤
- 总结
版本说明
- CentOS Linux release 7.6
方法步骤
- 执行命令
lsblk查询磁盘分区情况。
[root@... opt]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sr0 11:0 1 1024M 0 rom
xvda 202:0 0 40G 0 disk
├─xvda1 202:1 0 36G 0 part /
└─xvda2 202:2 0 4G 0 part [SWAP]
xvde 202:64 0 380G 0 disk
看见一块未分区的新磁盘 xvde。
- 执行磁盘分区命令
fdisk /dev/xvde，输入p打印分区表。
[root@... opt]# fdisk /dev/xvde
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 0x55a42d8e.
Command (m for help): p
Disk /dev/xvde: 408.0 GB, 408021893120 bytes, 796917760 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: 0x55a42d8e
Device Boot Start End Blocks Id System
- 执行命令
n创建一个 200G 大小的主分区。
Command (m for help): n
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p): p
Partition number (1-4, default 1):
First sector (2048-796917759, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-796917759, default 796917759): +200G
Partition 1 of type Linux and of size 200 GiB is set
- 执行命令
t修改分区类型为 Linux LVM（Logical Volume Manager，逻辑卷管理），注意：L可以查看所有可用的十六进制代码，Linux LVM 的十六进制代码是8e。
Command (m for help): t
Selected partition 1
Hex code (type L to list all codes): L
0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris
1 FAT12 27 Hidden NTFS Win 82 Linux swap / So c1 DRDOS/sec (FAT-
2 XENIX root 39 Plan 9 83 Linux c4 DRDOS/sec (FAT-
3 XENIX usr 3c PartitionMagic 84 OS/2 hidden C: c6 DRDOS/sec (FAT-
4 FAT16 <32M 40 Venix 80286 85 Linux extended c7 Syrinx
5 Extended 41 PPC PReP Boot 86 NTFS volume set da Non-FS data
6 FAT16 42 SFS 87 NTFS volume set db CP/M / CTOS / .
7 HPFS/NTFS/exFAT 4d QNX4.x 88 Linux plaintext de Dell Utility
8 AIX 4e QNX4.x 2nd part 8e Linux LVM df BootIt
9 AIX bootable 4f QNX4.x 3rd part 93 Amoeba e1 DOS access
a OS/2 Boot Manag 50 OnTrack DM 94 Amoeba BBT e3 DOS R/O
b W95 FAT32 51 OnTrack DM6 Aux 9f BSD/OS e4 SpeedStor
c W95 FAT32 (LBA) 52 CP/M a0 IBM Thinkpad hi eb BeOS fs
e W95 FAT16 (LBA) 53 OnTrack DM6 Aux a5 FreeBSD ee GPT
f W95 Ext'd (LBA) 54 OnTrackDM6 a6 OpenBSD ef EFI (FAT-12/16/
10 OPUS 55 EZ-Drive a7 NeXTSTEP f0 Linux/PA-RISC b
11 Hidden FAT12 56 Golden Bow a8 Darwin UFS f1 SpeedStor
12 Compaq diagnost 5c Priam Edisk a9 NetBSD f4 SpeedStor
14 Hidden FAT16 <3 61 SpeedStor ab Darwin boot f2 DOS secondary
16 Hidden FAT16 63 GNU HURD or Sys af HFS / HFS+ fb VMware VMFS
17 Hidden HPFS/NTF 64 Novell Netware b7 BSDI fs fc VMware VMKCORE
18 AST SmartSleep 65 Novell Netware b8 BSDI swap fd Linux raid auto
1b Hidden W95 FAT3 70 DiskSecure Mult bb Boot Wizard hid fe LANstep
1c Hidden W95 FAT3 75 PC/IX be Solaris boot ff BBT
1e Hidden W95 FAT1 80 Old Minix
Hex code (type L to list all codes): 8e
Changed type of partition 'Linux' to 'Linux LVM'
- 再次执行命令
p打印分区表，可见 Linux LVM 已经创建成功。
Command (m for help): p
Disk /dev/xvde: 408.0 GB, 408021893120 bytes, 796917760 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: 0x55a42d8e
Device Boot Start End Blocks Id System
/dev/xvde1 2048 419432447 209715200 8e Linux LVM
- 执行命令
wq写入并退出。
Command (m for help): wq
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
- 执行命令
pvcreate /dev/xvde1创建物理卷，执行pvscan和pvdisplay命令可以查看 pv 标志的物理分区。
[root@... opt]# pvcreate /dev/xvde1
Physical volume "/dev/xvde1" successfully created.
[root@... opt]# pvscan
PV /dev/xvde1 lvm2 [200.00 GiB]
Total: 1 [200.00 GiB] / in use: 0 [0 ] / in no VG: 1 [200.00 GiB]
[root@... opt]# pvdisplay
"/dev/xvde1" is a new physical volume of "200.00 GiB"
--- NEW Physical volume ---
PV Name /dev/xvde1
VG Name
PV Size 200.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID GrC5or-Jyr5-BEou-Zpzd-Sott-PSfx-5Hn9rt
- 执行命令
vgcreate opt /dev/xvde1创建卷组，其中opt是卷组名称，执行vgscan和vgdisplay命令可以查看卷组信息。
[root@... opt]# vgcreate opt /dev/xvde1
Volume group "opt" successfully created
[root@... opt]# vgscan
Reading volume groups from cache.
Found volume group "opt" using metadata type lvm2
[root@... opt]# vgdisplay
--- Volume group ---
VG Name opt
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 1
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 0
Open LV 0
Max PV 0
Cur PV 1
Act PV 1
VG Size <200.00 GiB
PE Size 4.00 MiB
Total PE 51199
Alloc PE / Size 0 / 0
Free PE / Size 51199 / <200.00 GiB
VG UUID 4ixgcF-nJ6u-XLcZ-esai-heup-l687-HnjZUG
- 执行命令
lvcreate -L 199G -n opt opt创建逻辑卷，-L表示从卷组中划分 199G 空间，-n表示后面第一个参数opt为逻辑卷名称，执行命令lvdisplay查询逻辑卷信息。
[root@... opt]# lvcreate -L 199G -n opt opt
Logical volume "opt" created.
[root@... opt]# lvdisplay
--- Logical volume ---
LV Path /dev/opt/opt
LV Name opt
VG Name opt
LV UUID tpsOd4-iDeL-82oO-HsYo-e3Kb-bGNN-XavB2X
LV Write Access read/write
LV Creation host, time ctuphicprc00342, 2019-11-21 20:41:39 +0800
LV Status available
# open 0
LV Size 199.00 GiB
Current LE 50944
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
- 执行命令
mkfs.ext4对逻辑卷进行格式化。
[root@... opt]# mkfs.ext4 /dev/opt/opt
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
13041664 inodes, 52166656 blocks
2608332 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2199912448
1592 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, 7962624, 11239424, 20480000, 23887872
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
- 执行命令
mount进行挂载，注意：要使挂载信息永久生效需要修改/etc/fstab文件，参考：CentOS 7.x 磁盘分区挂载。
[root@... opt]# mount /dev/opt/opt /opt
[root@... opt]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sr0 11:0 1 1024M 0 rom
xvda 202:0 0 40G 0 disk
├─xvda1 202:1 0 36G 0 part /
└─xvda2 202:2 0 4G 0 part [SWAP]
xvde 202:64 0 380G 0 disk
└─xvde1 202:65 0 200G 0 part
└─opt-opt 253:0 0 199G 0 lvm /opt
总结
创建 LVM 系统分区的主要步骤：
- 添加物理磁盘
- 创建新分区
- 创建 Physical Volume 物理卷
- 创建 Volume Group 卷组
- 创建 Logincal Volume 逻辑卷
- 格式化逻辑卷
- 挂载逻辑卷到指定目录
- 挂载信息写入
/etc/fstab
