- 之前在 VMware 安装 Ubuntu Server 的时候 磁盘分区 选择了 LVM，所以系统根目录默认占用磁盘大小只有4G，在安装软件时发现磁盘空间4G已经无法满足，所以需要利用 LVM 对磁盘进行扩容
- 查看文件系统磁盘空间的使用情况
root@ubuntu:~# df -h
Filesystem Size Used Avail Use% Mounted on
udev 451M 0 451M 0% /dev
tmpfs 97M 1.3M 96M 2% /run
/dev/mapper/ubuntu--vg-ubuntu--lv 3.9G 3.4G 287M 93% /
tmpfs 482M 0 482M 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 482M 0 482M 0% /sys/fs/cgroup
/dev/loop0 92M 92M 0 100% /snap/core/8689
/dev/loop1 90M 90M 0 100% /snap/core/8268
/dev/sda2 976M 77M 832M 9% /boot
tmpfs 97M 0 97M 0% /run/user/0
可以发现 /dev/mapper/ubuntu--vg-ubuntu--lv 虚拟机根目录空间只有3.9G，使用了93%。
- 查看LVM卷组的信息
root@ubuntu:~# vgdisplay
--- Volume group ---
VG Name ubuntu-vg
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 <19.00 GiB
PE Size 4.00 MiB
Total PE 4863
Alloc PE / Size 1024 / 4.00 GiB
Free PE / Size 3839 / <15.00 GiB
VG UUID hZPoxm-kSBU-fmKs-2yXD-hHoe-3T7e-PCIFSe
Free PE / Size 3839 / <15.00 GiB，这是还可以扩充的大小
- 使用命令进行磁盘扩容
lvextend -L 10G /dev/mapper/ubuntu--vg-ubuntu--lv //增大或减小至19G
lvextend -L +10G /dev/mapper/ubuntu--vg-ubuntu--lv //增加10G
lvreduce -L -10G /dev/mapper/ubuntu--vg-ubuntu--lv //减小10G
lvresize -l +100%FREE /dev/mapper/ubuntu--vg-ubuntu--lv //按百分比扩容
resize2fs /dev/mapper/ubuntu--vg-ubuntu--lv //重新调整逻辑卷大小
- 具体操作如下
// 按百分比进行磁盘扩容
root@ubuntu:~# lvextend -l +100%FREE /dev/mapper/ubuntu--vg-ubuntu--lv
Size of logical volume ubuntu-vg/ubuntu-lv changed from 4.00 GiB (1024 extents) to <19.00 GiB (4863 extents).
Logical volume ubuntu-vg/ubuntu-lv successfully resized.
// 刷新分区
root@ubuntu:~# resize2fs /dev/mapper/ubuntu--vg-ubuntu--lv
resize2fs 1.44.1 (24-Mar-2018)
Filesystem at /dev/mapper/ubuntu--vg-ubuntu--lv is mounted on /; on-line resizing required
old_desc_blocks = 3, new_desc_blocks = 3
The filesystem on /dev/mapper/ubuntu--vg-ubuntu--lv is now 4979712 (4k) blocks long.
// 查看文件系统磁盘空间的使用情况（发现此时已经扩容到19G）
root@ubuntu:~# df -h
Filesystem Size Used Avail Use% Mounted on
udev 451M 0 451M 0% /dev
tmpfs 97M 1.3M 96M 2% /run
/dev/mapper/ubuntu--vg-ubuntu--lv 19G 3.9G 14G 22% /
tmpfs 482M 0 482M 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 482M 0 482M 0% /sys/fs/cgroup
/dev/loop0 92M 92M 0 100% /snap/core/8689
/dev/loop1 90M 90M 0 100% /snap/core/8268
/dev/sda2 976M 77M 832M 9% /boot
tmpfs 97M 0 97M 0% /run/user/0
// 再次查看LVM卷组的信息（可扩容的空间已经成为0）
root@ubuntu:~# vgdisplay
--- Volume group ---
VG Name ubuntu-vg
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 4
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 <19.00 GiB
PE Size 4.00 MiB
Total PE 4863
Alloc PE / Size 4863 / <19.00 GiB
Free PE / Size 0 / 0
VG UUID hZPoxm-kSBU-fmKs-2yXD-hHoe-3T7e-PCIFSe
涉及的操作命令简单介绍：
- 查看块设备的信息 【-f】：显示每个块设备的文件系统类型（如ext4、NTFS、FAT32等）以及文件系统的标签（如果有）。
root@ubuntu:/home/michael# lsblk -f
NAME FSTYPE FSVER LABEL UUID FSAVAIL FSUSE% MOUNTPOINTS
loop0
squash 4.0 0 100% /snap/chromium/2497
loop1
squash 4.0 0 100% /snap/chromium/2529
loop2
squash 4.0 0 100% /snap/core20/1950
loop3
squash 4.0 0 100% /snap/core20/1974
loop4
squash 4.0 0 100% /snap/core22/806
loop5
squash 4.0 0 100% /snap/bare/5
loop6
squash 4.0 0 100% /snap/core22/817
loop7
squash 4.0 0 100% /snap/cups/974
loop8
squash 4.0 0 100% /snap/cups/980
loop9
squash 4.0 0 100% /snap/firefox/2908
loop10
squash 4.0 0 100% /snap/firefox/2850
loop11
squash 4.0 0 100% /snap/lxd/22753
loop12
squash 4.0 0 100% /snap/gnome-3-38-2004/140
loop13
squash 4.0 0 100% /snap/gtk-common-themes/1535
loop14
squash 4.0 0 100% /snap/gnome-3-38-2004/143
loop15
squash 4.0 0 100% /snap/snapd/19361
loop16
squash 4.0 0 100% /snap/lxd/24061
loop17
squash 4.0 0 100% /snap/snapd/19457
sda
├─sda1
│ ext2 1.0 0c16e136-b08b-48e6-beb1-27379362182b 417.3M 37% /boot
├─sda2
│
└─sda5
LVM2_m LVM2 qjGstm-EyqI-EL1p-tm6H-TZkq-tQt2-0Asw5u
├─ubuntu--vg-root
│ ext4 1.0 02df78f3-9fac-45f6-a163-bc25f8477529 19.2G 79% /var/snap/firefox/common/host-hunspell
│ /
└─ubuntu--vg-swap_1
swap 1 f1afd974-2f40-42f3-b9bc-a89da3b559d8 [SWAP]
sr0
- 显示物理卷的详细信息，包括物理卷的名称、大小、卷组、状态等。
root@ubuntu:/home/michael# pvdisplay
--- Physical volume ---
PV Name /dev/sda5
VG Name ubuntu-vg
PV Size 119.28 GiB / not usable 0
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 30536
Free PE 0
Allocated PE 30536
PV UUID qjGstm-EyqI-EL1p-tm6H-TZkq-tQt2-0Asw5u
- 显示卷组的详细信息，包括卷组的名称、物理卷数量、逻辑卷数量、总大小、空闲空间等。
root@ubuntu:/home/michael# vgdisplay
--- Volume group ---
VG Name ubuntu-vg
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 5
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 2
Open LV 2
Max PV 0
Cur PV 1
Act PV 1
VG Size 119.28 GiB
PE Size 4.00 MiB
Total PE 30536
Alloc PE / Size 30536 / 119.28 GiB
Free PE / Size 0 / 0
VG UUID xwbdQH-DBvq-qdzk-DQ3H-ofgA-0Y4B-Sl3FwF
- 显示逻辑卷的详细信息，比如逻辑卷的名称、大小、路径、状态等。
root@ubuntu:/home/michael# lvdisplay
--- Logical volume ---
LV Path /dev/ubuntu-vg/root
LV Name root
VG Name ubuntu-vg
LV UUID zIloDt-sa12-qqXk-7fKM-6Veu-09Pq-aedUBb
LV Write Access read/write
LV Creation host, time ubuntu, 2022-06-29 11:28:04 +0800
LV Status available
# open 1
LV Size <118.33 GiB
Current LE 30292
Segments 2
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:0
--- Logical volume ---
LV Path /dev/ubuntu-vg/swap_1
LV Name swap_1
VG Name ubuntu-vg
LV UUID di3eEs-oTyG-4u4z-JlVF-2P7a-6ke0-x6tIqx
LV Write Access read/write
LV Creation host, time ubuntu, 2022-06-29 11:28:04 +0800
LV Status available
# open 2
LV Size 976.00 MiB
Current LE 244
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:1
- 显示文件系统使用情况
- 【-h】：以易读的方式显示文件系统大小，将字节单位转换为更常见的千字节、兆字节和千兆字节。
- 【-T】：在输出中显示文件系统类型。
root@ubuntu:/home/michael# df -hT
Filesystem Type Size Used Avail Use% Mounted on
tmpfs tmpfs 791M 3.6M 787M 1% /run
/dev/mapper/ubuntu--vg-root ext4 117G 92G 20G 83% /
tmpfs tmpfs 3.9G 0 3.9G 0% /dev/shm
tmpfs tmpfs 5.0M 4.0K 5.0M 1% /run/lock
/dev/sda1 ext2 719M 265M 418M 39% /boot
tmpfs tmpfs 791M 116K 791M 1% /run/user/1000