LVM，分区扩容
2021-12-08 本文已影响0人
halfempty
1. 概述
LVM = Logical Volume Manager，直译为 “逻辑卷组管理”，它解决了常规磁盘分区大小无法伸缩的问题
磁盘 -> PV -> VG -> LV
- 每个磁盘分区对应一个物理卷组（PV）
- 多个物理卷组（PV）组成逻辑卷组（VG）
- 逻辑卷组（VG）划分给多个逻辑卷（LV）
image.png
2. 分区扩容
2.1. 磁盘 -> PV
# 查看系统磁盘，有/dev/vda 和 /dev/vdb 共2个物理分区
[root@bd107 ~]# fdisk -l
Disk /dev/vda: 42.9 GB, 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 label type: dos
Disk identifier: 0x00099229
Device Boot Start End Blocks Id System
/dev/vda1 * 2048 2099199 1048576 83 Linux
/dev/vda2 2099200 83886079 40893440 8e Linux LVM
Disk /dev/mapper/cl-root: 536.9 GB, 536870912000 bytes, 1048576000 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/cl-swap: 4160 MB, 4160749568 bytes, 8126464 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/vdb: 536.9 GB, 536870912000 bytes, 1048576000 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
# 磁盘转PV
pvcreate /dev/vdb
2.2. PV -> VG
# 查看vg命名空间，名称为cl
[root@bd107 ~]# vgdisplay
--- Volume group ---
VG Name cl
System ID
Format lvm2
Metadata Areas 2
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 2
Act PV 2
VG Size 538.99 GiB
PE Size 4.00 MiB
Total PE 137982
Alloc PE / Size 128992 / 503.88 GiB
Free PE / Size 8990 / 35.12 GiB
VG UUID T7Ovhi-Mk5V-Ry9y-s8RV-9ihc-pvgq-am0g0V
# 将2.1步创建的pv加入到cl
vgextend cl /dev/vdb
2.3. VG -> LV
# 查看逻辑卷路径，其中根分区路径为/dev/cl/root
[root@bd107 ~]# lvdisplay
--- Logical volume ---
LV Path /dev/cl/swap
LV Name swap
VG Name cl
LV UUID QCN8wW-Ic4K-l3SM-LRYF-2t06-K6wM-AQoOlK
LV Write Access read/write
LV Creation host, time 172-31-128-183, 2021-06-07 17:12:59 +0800
LV Status available
# open 2
LV Size 3.88 GiB
Current LE 992
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:1
--- Logical volume ---
LV Path /dev/cl/root
LV Name root
VG Name cl
LV UUID WFIxvP-BIkN-CIJt-6UQY-kn6D-iqu1-c4n2HL
LV Write Access read/write
LV Creation host, time 172-31-128-183, 2021-06-07 17:12:59 +0800
LV Status available
# open 1
LV Size 500.00 GiB
Current LE 128000
Segments 2
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
# 扩展根分区大小
lvextend -l 100%FREE /dev/cl/root /dev/vdb
2.4. 刷新分区
适用于centos7版本
xfs_growfs /
