前言：
目前同学们对“ubuntu扩展分区大小”可能比较关怀，大家都想要了解一些“ubuntu扩展分区大小”的相关内容。那么小编在网上网罗了一些对于“ubuntu扩展分区大小””的相关知识，希望朋友们能喜欢，大家快快来学习一下吧！如果服务器的磁盘空间不够怎么办？没关系，我们可以使用LVM技术来对服务器进行扩容。
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，它由Heinz Mauelshagen在Linux 2.4内核上实现，目前最新版本为：稳定版1.0.5，开发版 1.1.0-rc2，以及LVM2开发版。LVM是在磁盘分区和文件系统之间添加的一个逻辑层，来为文件系统屏蔽下层磁盘分区布局，提供一个抽象的存储卷，在存储卷上建立文件系统。首先我们讨论以下几个LVM术语：
● 物理卷Physical Volume (PV):可以在 上面建立卷组的媒介,可以是硬盘分区，也可以是硬盘本身或者回环文件(loopbackfle) .物理卷包括一个特殊的 header,其余部分被切割为-块块物理区域 (physicalextents)
●卷组Volume group (VG):将-组物理卷收集为- 个管理单元
●逻辑卷Logical volume (LV):虚拟分区， 由物理区域(physical extents)组成
●物理区域Physical extent (PE):硬盘可供指派给逻辑卷的最小单位(通常为4MB)
LVM抽象模型
理解了以上概念后，我们来实际操作体验一下：
首先，在虚拟机上增加一块40G的磁盘，如下图：
增加一块40G的硬盘
然后，我们按以下操作步骤进行扩容
查看挂载点df -h
Filesystem Size Used Avail Use% Mounted on
udev 955M 0 955M 0% /dev
tmpfs 198M 904K 197M 1% /run
/dev/mapper/ubuntu--vg-ubuntu--lv 19G 3.8G 14G 22% /
tmpfs 986M 0 986M 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 986M 0 986M 0% /sys/fs/cgroup
/dev/sda2 976M 78M 832M 9% /boot
tmpfs 198M 0 198M 0% /run/user/1000
显示当前的Logical volume (LV): lvdisplay
root@ubuntu:~# lvdisplay --- Logical volume --- LV Path /dev/ubuntu-vg/ubuntu-lv LV Name ubuntu-lv VG Name ubuntu-vg LV UUID qPS9DH-4ceg-o56l-qWdh-XhXI-mg2v-ZSC4R3 LV Write Access read/write LV Creation host, time ubuntu-server, 2020-11-26 10:45:50 +0800 LV Status available # open 1 LV Size <19.00 GiB Current LE 4863 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0显示当前的Volume group (VG)：vgdisplay
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 4863 / <19.00 GiB Free PE / Size 0 / 0 VG UUID 1dYOYx-Z0T7-nJ0I-A8hV-OPwr-h5dj-Ep2le7显示当前的Physical Volume (PV)：pvdisplayroot@ubuntu:~# pvdisplay
--- Physical volume ---
PV Name /dev/sda3
VG Name ubuntu-vg
PV Size <19.00 GiB / not usable 0
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 4863
Free PE 0
Allocated PE 4863
PV UUID y4Zxi2-al2M-6wOf-SrnQ-L1vT-fuls-HIRf2h
开始LVM扩容
查看fdiskfdisk -l
root@ubuntu:~# fdisk -l
Disk /dev/sda: 20 GiB, 21474836480 bytes, 41943040 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
Disklabel type: gpt
Disk identifier: C57D49AC-9DB7-42B8-BE6A-7FA61C9C868E
Device Start End Sectors Size Type
/dev/sda1 2048 4095 2048 1M BIOS boot
/dev/sda2 4096 2101247 2097152 1G Linux filesystem
/dev/sda3 2101248 41940991 39839744 19G Linux filesystem
Disk /dev/sdb: 40 GiB, 42949672960 bytes, 83886080 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 /dev/mapper/ubuntu--vg-ubuntu--lv: 19 GiB, 20396900352 bytes, 39837696 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
root@ubuntu:~#
查看所有储存设备fdisk -l |grep '/dev'
root@ubuntu:~# fdisk -l |grep '/dev'
Disk /dev/sda: 20 GiB, 21474836480 bytes, 41943040 sectors
/dev/sda1 2048 4095 2048 1M BIOS boot
/dev/sda2 4096 2101247 2097152 1G Linux filesystem
/dev/sda3 2101248 41940991 39839744 19G Linux filesystem
Disk /dev/sdb: 40 GiB, 42949672960 bytes, 83886080 sectors
Disk /dev/mapper/ubuntu--vg-ubuntu--lv: 19 GiB, 20396900352 bytes, 39837696 sectors创建sdb分区fdisk /dev/sdb
root@ubuntu:~# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.31.1).
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.
Created a new DOS disklabel with disk identifier 0x41160c4b.
Command (m for help):
Command (m for help): n
Partition type
p primary (0 primary, 0 extended, 4 free)
e extended (container for logical partitions)
Select (default p): p
Partition number (1-4, default 1):
First sector (2048-83886079, default 2048):
Last sector, +sectors or +size{K,M,G,T,P} (2048-83886079, default 83886079):
Created a new partition 1 of type 'Linux' and of size 40 GiB.
Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
格式化mkfs -t ext4 /dev/sdb1
root@ubuntu:~# mkfs -t ext4 /dev/sdb1
mke2fs 1.44.1 (24-Mar-2018)
Creating filesystem with 10485504 4k blocks and 2621440 inodes
Filesystem UUID: ab33e7a7-0348-48a4-9a96-a2c19876dd98
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624
Allocating group tables: done
Writing inode tables: done
Creating journal (65536 blocks): done
Writing superblocks and filesystem accounting information: done创建PVpvcreate /dev/sdb1
root@ubuntu:~# pvcreate /dev/sdb1
WARNING: ext4 signature detected on /dev/sdb1 at offset 1080. Wipe it? [y/n]: y
Wiping ext4 signature on /dev/sdb1.
Physical volume "/dev/sdb1" successfully created.
查看卷组pvscan
root@ubuntu:~# pvscan
PV /dev/sda3 VG ubuntu-vg lvm2 [<19.00 GiB / 0 free]
PV /dev/sdb1 lvm2 [<40.00 GiB]
Total: 2 [<59.00 GiB] / in use: 1 [<19.00 GiB] / in no VG: 1 [<40.00 GiB]
扩容VG查看VGvgdisplay
--- 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 4863 / <19.00 GiB
Free PE / Size 0 / 0
VG UUID 1dYOYx-Z0T7-nJ0I-A8hV-OPwr-h5dj-Ep2le7
扩容VGvgextend ubuntu-vg /dev/sdb1
root@ubuntu:~# vgextend ubuntu-vg /dev/sdb1
Volume group "ubuntu-vg" successfully extended
root@ubuntu:~# pvscan
PV /dev/sda3 VG ubuntu-vg lvm2 [<19.00 GiB / 0 free]
PV /dev/sdb1 VG ubuntu-vg lvm2 [<40.00 GiB / <40.00 GiB free]
Total: 2 [58.99 GiB] / in use: 2 [58.99 GiB] / in no VG: 0 [0 ]
root@ubuntu:~# 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 58.99 GiB
PE Size 4.00 MiB
Total PE 15102
Alloc PE / Size 4863 / <19.00 GiB
Free PE / Size 10239 / <40.00 GiB
VG UUID 1dYOYx-Z0T7-nJ0I-A8hV-OPwr-h5dj-Ep2le7
root@ubuntu:~# lvdisplay
--- Logical volume ---
LV Path /dev/ubuntu-vg/ubuntu-lv
LV Name ubuntu-lv
VG Name ubuntu-vg
LV UUID qPS9DH-4ceg-o56l-qWdh-XhXI-mg2v-ZSC4R3
LV Write Access read/write
LV Creation host, time ubuntu-server, 2020-11-26 10:45:50 +0800
LV Status available
# open 1
LV Size <19.00 GiB
Current LE 4863
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:0
扩容LV#按固定大小追加
lvextend -L +10G /dev/ubuntu-vg/ubuntu-lv
#按百分比追加
lvextend -l +100%FREE /dev/ubuntu-vg/ubuntu-lv
root@ubuntu:~# lvextend -L +10G /dev/ubuntu-vg/ubuntu-lv
Size of logical volume ubuntu-vg/ubuntu-lv changed from <19.00 GiB (4863 extents) to <29.00 GiB (7423 extents).
Logical volume ubuntu-vg/ubuntu-lv successfully resized.
root@ubuntu:~# lvextend -l +100%FREE /dev/ubuntu-vg/ubuntu-lv
Size of logical volume ubuntu-vg/ubuntu-lv changed from <29.00 GiB (7423 extents) to 58.99 GiB (15102 extents).
Logical volume ubuntu-vg/ubuntu-lv successfully resized.刷新分区resize2fs /dev/ubuntu-vg/ubuntu-lv
root@ubuntu:~# resize2fs /dev/ubuntu-vg/ubuntu-lv
resize2fs 1.44.1 (24-Mar-2018)
Filesystem at /dev/ubuntu-vg/ubuntu-lv is mounted on /; on-line resizing required
old_desc_blocks = 3, new_desc_blocks = 4
The filesystem on /dev/ubuntu-vg/ubuntu-lv is now 7601152 (4k) blocks long.
验证是否成功lvdisplay
root@ubuntu:~# lvdisplay
--- Logical volume ---
LV Path /dev/ubuntu-vg/ubuntu-lv
LV Name ubuntu-lv
VG Name ubuntu-vg
LV UUID qPS9DH-4ceg-o56l-qWdh-XhXI-mg2v-ZSC4R3
LV Write Access read/write
LV Creation host, time ubuntu-server, 2020-11-26 10:45:50 +0800
LV Status available
# open 1
LV Size 58.99 GiB
Current LE 15102
Segments 2
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:0
root@ubuntu:~# vgdisplay
--- Volume group ---
VG Name ubuntu-vg
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 5
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 58.99 GiB
PE Size 4.00 MiB
Total PE 15102
Alloc PE / Size 15102 / 58.99 GiB
Free PE / Size 0 / 0
VG UUID 1dYOYx-Z0T7-nJ0I-A8hV-OPwr-h5dj-Ep2le7
df -h
root@ubuntu:~# df -h
Filesystem Size Used Avail Use% Mounted on
udev 955M 0 955M 0% /dev
tmpfs 198M 908K 197M 1% /run
/dev/mapper/ubuntu--vg-ubuntu--lv 58G 3.9G 52G 7% /
tmpfs 986M 0 986M 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 986M 0 986M 0% /sys/fs/cgroup
/dev/sda2 976M 78M 832M 9% /boot
tmpfs 198M 0 198M 0% /run/user/0
最后，我们成功的扩展了40G磁盘空间。
标签： #ubuntu扩展分区大小
