在我們安裝ubuntu時，如果選擇的是自動分區，就會按照邏輯卷的形式來分區，并且只分配100G其余的并不會被分配，這對我們大多數情況來說都是不合理的，所以，如何擴充呢

下面以一個小的案例來說明如何擴充

問題

磁盤空間已滿

Usage of /: 99.8% of 9.75GB

df、fdisk查看磁盤占用情況

df -h

root@summergao:~# df -h
Filesystem                         Size  Used Avail Use% Mounted on
udev                                16G     0   16G   0% /dev
tmpfs                              3.2G  2.2M  3.2G   1% /run
/dev/mapper/ubuntu--vg-ubuntu--lv   98G   97G   0G  100% /
tmpfs                               16G     0   16G   0% /dev/shm
tmpfs                              5.0M     0  5.0M   0% /run/lock
tmpfs                               16G     0   16G   0% /sys/fs/cgroup
/dev/loop0                          64M   64M     0 100% /snap/core20/1828
/dev/loop2                          50M   50M     0 100% /snap/snapd/18357
/dev/loop1                          92M   92M     0 100% /snap/lxd/24061
/dev/sda2                          2.0G  112M  1.7G   7% /boot
/dev/sda1                          1.1G  6.1M  1.1G   1% /boot/efi
tmpfs                              3.2G     0  3.2G   0% /run/user/0
root@summergao:~# 

fdisk -l

root@summergao:~# fdisk -l
Disk /dev/loop0: 63.29 MiB, 66359296 bytes, 129608 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytesDisk /dev/loop1: 91.85 MiB, 96292864 bytes, 188072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytesDisk /dev/loop2: 49.86 MiB, 52260864 bytes, 102072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytesDisk /dev/sda: 9.1 TiB, 10000294477824 bytes, 19531825152 sectors
Disk model: PERC H330 Mini  
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: FCB82ED5-B67D-4AF4-914E-1045C910D2E7Device       Start         End     Sectors  Size Type
/dev/sda1     2048     2203647     2201600  1.1G EFI System
/dev/sda2  2203648     6397951     4194304    2G Linux filesystem
/dev/sda3  6397952 19531823103 19525425152  9.1T Linux filesystemDisk /dev/mapper/ubuntu--vg-ubuntu--lv: 100 GiB, 107374182400 bytes, 209715200 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
root@summergao:~#

查看磁盤掛載情況

lsblk

root@summergao:~# lsblk
NAME                      MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
loop0                       7:0    0 63.3M  1 loop /snap/core20/1828
loop1                       7:1    0 91.9M  1 loop /snap/lxd/24061
loop2                       7:2    0 49.9M  1 loop /snap/snapd/18357
sda                         8:0    0  9.1T  0 disk 
├─sda1                      8:1    0  1.1G  0 part /boot/efi
├─sda2                      8:2    0    2G  0 part /boot
└─sda3                      8:3    0  9.1T  0 part └─ubuntu--vg-ubuntu--lv 253:0    0  100G  0 lvm  /
sr0                        11:0    1 1024M  0 rom  
root@summergao:~# 

可以看到sda3有9.1T，但是只分配了100G。

命令vgdisplay可以查看lvm卷組的信息

root@summergao:~# vgdisplay--- Volume group ---VG Name               ubuntu-vgSystem ID             Format                lvm2Metadata Areas        1Metadata Sequence No  2VG Access             read/writeVG Status             resizableMAX LV                0Cur LV                1Open LV               1Max PV                0Cur PV                1Act PV                1VG Size               9.09 TiBPE Size               4.00 MiBTotal PE              2383474Alloc PE / Size       25600 / 100.00 GiBFree  PE / Size       2357874 / 8.99 TiBVG UUID               tsCO25-L5Rx-2qGn-2l1e-6vl0-fjJl-HaweHlroot@summergao:~#

如果看到 Free PE / Size > 0，表示還有擴容空間。

Free ?PE / Size ? ? ? 2357874 / 8.99 TiB?這是還可以擴容的大小 。

解決辦法

使用命令進行磁盤擴容

擴容指令示例如下：

#lvextend -L +10G /dev/mapper/ubuntu--vg-ubuntu--lv          //增加10G
#lvreduce -L -10G /dev/mapper/ubuntu--vg-ubuntu--lv          //減小10G
#lvresize -l  +100%FREE /dev/mapper/ubuntu--vg-ubuntu--lv    //按百分比擴

這里選擇將所有空閑磁盤全部用來擴容

lvresize -l  +100%FREE /dev/mapper/ubuntu--vg-ubuntu--lv

root@summergao:~# lvresize -l  +100%FREE /dev/mapper/ubuntu--vg-ubuntu--lvSize of logical volume ubuntu-vg/ubuntu-lv changed from 100.00 GiB (25600 extents) to 9.09 TiB (2383474 extents).Logical volume ubuntu-vg/ubuntu-lv successfully resized.
root@summergao:~# 

執行resize2fs使擴容生效 （注意：不執行這個命令以上修改是不會生效的！）

resize2fs /dev/mapper/ubuntu--vg-ubuntu--lv

root@summergao:~# resize2fs /dev/mapper/ubuntu--vg-ubuntu--lv
resize2fs 1.45.5 (07-Jan-2020)
Filesystem at /dev/mapper/ubuntu--vg-ubuntu--lv is mounted on /; on-line resizing required
old_desc_blocks = 13, new_desc_blocks = 1164
The filesystem on /dev/mapper/ubuntu--vg-ubuntu--lv is now 2440677376 (4k) blocks long.root@summergao:~# 

查看擴容結果

再次查看LVM卷組的信息，以及分區空間大小

vgdisplay

root@summergao:~# vgdisplay--- Volume group ---VG Name               ubuntu-vgSystem ID             Format                lvm2Metadata Areas        1Metadata Sequence No  3VG Access             read/writeVG Status             resizableMAX LV                0Cur LV                1Open LV               1Max PV                0Cur PV                1Act PV                1VG Size               9.09 TiBPE Size               4.00 MiBTotal PE              2383474Alloc PE / Size       2383474 / 9.09 TiBFree  PE / Size       0 / 0   VG UUID               tsCO25-L5Rx-2qGn-2l1e-6vl0-fjJl-HaweHl

可以看到此時Free PE / Size 已經為0了

df -h 

root@summergao:~# df -h
Filesystem                         Size  Used Avail Use% Mounted on
udev                                16G     0   16G   0% /dev
tmpfs                              3.2G  2.2M  3.2G   1% /run
/dev/mapper/ubuntu--vg-ubuntu--lv  9.0T   11G  8.6T   1% /
tmpfs                               16G     0   16G   0% /dev/shm
tmpfs                              5.0M     0  5.0M   0% /run/lock
tmpfs                               16G     0   16G   0% /sys/fs/cgroup
/dev/loop0                          64M   64M     0 100% /snap/core20/1828
/dev/loop2                          50M   50M     0 100% /snap/snapd/18357
/dev/loop1                          92M   92M     0 100% /snap/lxd/24061
/dev/sda2                          2.0G  112M  1.7G   7% /boot
/dev/sda1                          1.1G  6.1M  1.1G   1% /boot/efi
tmpfs                              3.2G     0  3.2G   0% /run/user/0
root@summergao:~# 

查看當前磁盤大小已經擴容到9.0T了

參考

ubuntu的ubuntu--vg-ubuntu--lv磁盤擴容 - 厚禮蝎 - 博客園

ubuntu server版 虛擬機根目錄磁盤擴容_ubuntu--vg-ubuntu--lv只有100g-CSDN博客