LVM简介
LVM是 Logical Volume Manager（逻辑卷管理）的简写，它是Linux环境下对磁盘分区进行管理的一种机制。LVM将一个或多个磁盘分区（PV）虚拟为一个卷组（VG），相当于一个大的硬盘，我们可以在上面划分一些逻辑卷（LV）。当卷组的空间不够使用时，可以将新的磁盘分区加入进来。我们还可以从卷组剩余空间上划分一些空间给空间不够用的逻辑卷使用。
需求
虚拟机目前只有一块 40G 的硬盘，所以存储不够用了，需要扩容，但是 Ubuntu 使用的是 LVM 来管理硬盘，所以我们需要将添加的硬盘使用 LVM 卷管理来扩容存储空间。
添加硬盘
bash
root@master:~# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS
loop0
7:0 0 18.8M 1 loop /snap/k9s/155
loop1
7:1 0 38.8M 1 loop /snap/snapd/21759
loop2
7:2 0 63.9M 1 loop /snap/core20/2318
sr0 11:0 1 1024M 0 rom
vda 252:0 0 40G 0 disk
├─vda1
│ 252:1 0 1M 0 part
├─vda2
│ 252:2 0 2G 0 part /boot
└─vda3
252:3 0 38G 0 part
└─ubuntu--vg-ubuntu--lv
253:0 0 88G 0 lvm /var/lib/kubelet/pods/c0acc691-ab06-4573-aa64-98ac3aca0ad6/volume-subpaths/jenkins-pv-volume/jenkins/0
/var/lib/kubelet/pods/4359357c-5b61-4981-84e7-73271d1c88a5/volume-subpaths/tigera-ca-bundle/calico-kube-controllers/1
/var/lib/kubelet/pods/f48ab3ae-0eaa-44dd-97bd-4488c2b4def1/volume-subpaths/tigera-ca-bundle/calico-node/1
/var/lib/kubelet/pods/e7f67447-d801-4eb5-b78c-3dd4ff0e7c24/volume-subpaths/tigera-ca-bundle/calico-typha/1
/var/lib/kubelet/pods/c0acc691-ab06-4573-aa64-98ac3aca0ad6/volumes/kubernetes.io~local-volume/jenkins-pv-volume
/
vdb 252:16 0 50G 0 disk可以看到我添加了一块硬盘vdb，拥有 50G 的空间
对新硬盘分区
这里我们使用 fdisk 工具来进行交互式分区
bash
# fdisk /dev/vdb #执行此命令，进行分区
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 0xdf09eb6a.
Command (m for help): p #在此输入p
Disk /dev/vdb: 214.7 GB, 214748364800 bytes, 419430400 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: 0xdf09eb6a
Device Boot Start End Blocks Id System
Command (m for help): n #在此输入n
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p): p
Partition number (1-4, default 1): 1 #在此输入1
First sector (2048-419430399, default 2048): #回车
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-419430399, default 419430399): #回车
Using default value 419430399
Partition 1 of type Linux and of size 200 GiB is set
Command (m for help): t #在此输入t
Selected partition 1
Hex code (type L to list all codes): L #在此输入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 #输入lvm类型的hex代码
Changed type of partition 'Linux' to 'Linux LVM'
Command (m for help): p #在此输入p
Disk /dev/vdb: 214.7 GB, 214748364800 bytes, 419430400 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: 0xdf09eb6a
Device Boot Start End Blocks Id System
/dev/vdb1 2048 419430399 209714176 8e Linux LVM
Command (m for help): w #保存
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.创建物理卷PV
通过 lsblk 可以看到vdb 硬盘已经有了一个 vdb1 的分区
bash
vdb 252:16 0 50G 0 disk
└─vdb1接下来需要用这个分区创建一个物理卷
bash
# pvcreate /dev/vdb1
Physical volume "/dev/sdb1" successfully created.插卡看看你物理卷
bash
root@master:~/kubevirt# pvdisplay
--- Physical volume ---
PV Name /dev/vda3
VG Name ubuntu-vg
PV Size <38.00 GiB / not usable 0
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 9727
Free PE 0
Allocated PE 9727
PV UUID vbb5h2-G2mh-bxwo-Fvbu-YHMc-w0ox-j5tDU7
"/dev/vdb1" is a new physical volume of "<50.00 GiB"
--- NEW Physical volume --- #这就是刚创建的物理卷
PV Name /dev/vdb1
VG Name
PV Size <50.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID ksuLmo-uwJI-olt3-w2qo-ZOIZ-IuPJ-ge4AFT将物理卷PV加入卷组VG
查看卷组
bash
root@master:~/kubevirt# vgdisplay
--- Volume group ---
VG Name ubuntu-vg #卷组名
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 2
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 1
Act PV 1
VG Size <38.00 GiB
PE Size 4.00 MiB
Total PE 9727
Alloc PE / Size 9727 / <38.00 GiB
Free PE / Size 0 / 0
VG UUID yYRukh-rHIp-EmtX-TePI-00i3-Aizq-ttSV8V将新的分区/dev/vdb1加入到卷组中，这里的卷组名为ubuntu-vg
root@master:~/kubevirt# vgextend ubuntu-vg /dev/vdb1
Volume group "ubuntu-vg" successfully extended添加完成后再次查看卷组信息
bash
root@master:~/kubevirt# vgdisplay
--- Volume group ---
VG Name ubuntu-vg
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 3
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 1
Open LV 1
Max PV 0
Cur PV 2
Act PV 2
VG Size 87.99 GiB
PE Size 4.00 MiB
Total PE 22526
Alloc PE / Size 9727 / <38.00 GiB
Free PE / Size 12799 / <50.00 GiB
VG UUID yYRukh-rHIp-EmtX-TePI-00i3-Aizq-ttSV8V扩容已有分区
下面是对现有分区进行逻辑卷扩容，我们这里根分区为40G，我们准备扩容根分区查看根分区的LV路径
bash
root@master:~/kubevirt# df -h
Filesystem Size Used Avail Use% Mounted on
tmpfs 392M 4.1M 388M 2% /run
/dev/mapper/ubuntu--vg-ubuntu--lv 38G 21G 15G 59% /
tmpfs 2.0G 0 2.0G 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 2.0G 0 2.0G 0% /run/qemu
/dev/vda2 2.0G 129M 1.7G 8% /boot
#省略...扩容卷/dev/mapper/ubuntu--vg-ubuntu--lv
bash
root@master:~/kubevirt# lvextend -l +100%FREE /dev/mapper/ubuntu--vg-ubuntu--lv
Size of logical volume ubuntu-vg/ubuntu-lv changed from <38.00 GiB (9727 extents) to 87.99 GiB (22526 extents).
Logical volume ubuntu-vg/ubuntu-lv successfully resized.查看扩容后的逻辑卷大小
bash
root@master:~/kubevirt# lvdisplay /dev/mapper/ubuntu--vg-ubuntu--lv
--- Logical volume ---
LV Path /dev/ubuntu-vg/ubuntu-lv
LV Name ubuntu-lv
VG Name ubuntu-vg
LV UUID Tzdcm9-Z7YL-TmBZ-puFe-6e77-eB9X-F9Q3xo
LV Write Access read/write
LV Creation host, time ubuntu-server, 2024-05-14 02:40:50 +0000
LV Status available
# open 1
LV Size 87.99 GiB
Current LE 22526
Segments 2
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:0然后使用resize2fs进行在线调整xfs格式的文件系统大小
bash
root@master:~# resize2fs /dev/mapper/ubuntu--vg-ubuntu--lv
resize2fs 1.46.5 (30-Dec-2021)
Filesystem at /dev/mapper/ubuntu--vg-ubuntu--lv is mounted on /; on-line resizing required
old_desc_blocks = 5, new_desc_blocks = 11
The filesystem on /dev/mapper/ubuntu--vg-ubuntu--lv is now 23066624 (4k) blocks long.最后查看下根分区的大小是否扩容成功
bash
root@master:~# df -Th
Filesystem Type Size Used Avail Use% Mounted on
tmpfs tmpfs 392M 3.9M 388M 1% /run
/dev/mapper/ubuntu--vg-ubuntu--lv ext4 87G 21G 62G 26% /
tmpfs tmpfs 2.0G 0 2.0G 0% /dev/shm
tmpfs tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs tmpfs 2.0G 0 2.0G 0% /run/qemu
/dev/vda2 ext4 2.0G 129M 1.7G 8% /boot
#省略...可以看到已经完成了 LVM 卷的扩容！
