LVM是 Logical Volume Manager（邏輯卷管理）的簡寫，它是Linux環境下對磁盤分區進行管理的一種機制，用戶可以在無需停機的情況下可以方便地調整各個分區大小。
LVM名詞：
物理卷（Physical Volume，PV）：包含LVM信息的分區、磁盤
物理卷組（Volume Group，VG）：多個物理卷組成，可以在VG上創建一個或多個LV
邏輯卷（Logical Volume，LV）：創建在VG上的分區，可以在LV上創建文件系統
物理塊（Physical Extent，PE）：物理卷的基本單元，PV=PE*數量
創建LVM：
查看命令：
pvs|pvdisplay ##查看物理卷
vgs|vgdisplay ##查看物理卷組
lvs|lvdisplay ##查看邏輯卷
##測試前我們可以使用watch命令監控測試的變化
[root@server ~]# watch -n 1 'pvs;vgs;lvs;df -h /mnt'
##測試用的虛擬機準備了三塊磁盤vdb、vdc、vdd，並且都創建了LVM分區
不會創建的可以參考https://blog.csdn.net/xin1889/article/details/80171516
[root@server ~]# parted
GNU Parted 3.1
Using /dev/vda
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) print list
Model: Virtio Block Device (virtblk)
Disk /dev/vda: 10.7GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 10.7GB 10.7GB primary xfs boot
Model: Virtio Block Device (virtblk)
Disk /dev/vdb: 10.7GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 10.7GB 10.7GB primary lvm
Model: Virtio Block Device (virtblk)
Disk /dev/vdc: 10.7GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 10.7GB 10.7GB primary lvm
Model: Virtio Block Device (virtblk)
Disk /dev/vdd: 10.7GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 10.7GB 10.7GB primary lvm
創建LVM
創建命令：
pvcreate ##將物理分區製作成物理卷（pv）
vgcreate ##用製作好的物理卷製作一個物理卷組（vg）
lvcreate ##在物理卷組（vg）中創建lv設備，-L 指定大小，-n 指定設備名稱
[root@server ~]# pvcreate /dev/vdb1 ##將分區/dev/vdb1創建成pv
Physical volume "/dev/vdb1" successfully created
[root@server ~]# vgcreate vg0 /dev/vdb1 / ##將pv製作成一個vg
Volume group "vg0" successfully created
[root@server ~]# lvcreate -L 8G -n lv0 vg0 ##在vg上創建一個lv
Logical volume "lv0" created
[root@server ~]# mkfs.xfs /dev/vg0/lv0 ##格式化
meta-data=/dev/vg0/lv0 isize=256 agcount=4, agsize=524288 blks
= sectsz=512 attr=2, projid32bit=1
= crc=0
data = bsize=4096 blocks=2097152, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=0
log =internal log bsize=4096 blocks=2560, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
[root@server ~]# mount /dev/vg0/lv0 /mnt/ ##掛載
####監控內容####
Every 1.0s: pvs;vgs;lvs;df -h /mnt Wed May 9 09:35:31 2018
PV VG Fmt Attr PSize PFree
/dev/vdb1 vg0 lvm2 a-- 10.00g 2.00g
VG #PV #LV #SN Attr VSize VFree
vg0 1 1 0 wz--n- 10.00g 2.00g
LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert
lv0 vg0 -wi-ao---- 8.00g
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg0-lv0 8.0G 33M 8.0G 1% /mnt
擴充LVM
[root@server ~]# pvcreate /dev/vdc1 ##將/dev/vdc1製作成物理卷
Physical volume "/dev/vdd1" successfully created
[root@server ~]# vgextend vg0 /dev/vdc1 ##將/dev/vdc1添加至vg0
Volume group "vg0" successfully extended
[root@server ~]# lvextend -L 12G /dev/vg0/lv0 ##將lv0擴大至12G
Extending logical volume lv0 to 12.00 GiB
Logical volume lv0 successfully resized
[root@server ~]# xfs_growfs /dev/vg0/lv0 ##將文件系統擴大至lv0大小
meta-data=/dev/mapper/vg0-lv0 isize=256 agcount=4, agsize=524288 blks
= sectsz=512 attr=2, projid32bit=1
= crc=0
data = bsize=4096 blocks=2097152, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=0
log =internal bsize=4096 blocks=2560, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 2097152 to 3145728
####監控內容####
Every 1.0s: pvs;vgs;lvs;df -h /mnt Wed May 9 09:42:31 2018
PV VG Fmt Attr PSize PFree
/dev/vdb1 vg0 lvm2 a-- 10.00g 0
/dev/vdc1 vg0 lvm2 a-- 10.00g 7.99g
VG #PV #LV #SN Attr VSize VFree
vg0 2 1 0 wz--n- 19.99g 7.99g
LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert
lv0 vg0 -wi-ao---- 12.00g
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg0-lv0 12G 33M 12G 1% /mnt
####xfs文件系統只能擴大，不能縮小，如果日後需要縮減，需要使用ext文件格式####
[root@server ~]# umount /dev/vg0/lv0 ##解除掛載
[root@server ~]# mkfs.ext4 /dev/vg0/lv0 ##格式化成ext4格式
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
786432 inodes, 3145728 blocks
157286 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2151677952
96 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208
[root@server ~]# mount /dev/vg0/lv0 /mnt/ ##重新掛載
[root@server ~]# lvextend -L 15G /dev/vg0/lv0 ##擴大lv0到15G大小
Extending logical volume lv0 to 15.00 GiB
Logical volume lv0 successfully resized
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
[root@server ~]# resize2fs /dev/vg0/lv0 ##擴展ext4文件系統到lv大小
resize2fs 1.42.9 (28-Dec-2013)
Filesystem at /dev/vg0/lv0 is mounted on /mnt; on-line resizing required
old_desc_blocks = 2, new_desc_blocks = 2
The filesystem on /dev/vg0/lv0 is now 3932160 blocks long.
####監控內容####
Every 1.0s: pvs;vgs;lvs;df -h /mnt Wed May 9 09:53:31 2018
PV VG Fmt Attr PSize PFree
/dev/vdb1 vg0 lvm2 a-- 10.00g 0
/dev/vdc1 vg0 lvm2 a-- 10.00g 4.99g
VG #PV #LV #SN Attr VSize VFree
vg0 2 1 0 wz--n- 19.99g 4.99g
LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert
lv0 vg0 -wi-ao---- 15.00g
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg0-lv0 15G 41M 14G 1% /mnt
LVM縮減
[root@server ~]# umount /dev/vg0/lv0 ##解除掛載
[root@server ~]# e2fsck -f /dev/vg0/lv0 ##掃描文件系統中已經存在的數據
e2fsck 1.42.9 (28-Dec-2013)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
/dev/vg0/lv0: 11/983040 files (0.0% non-contiguous), 104724/3932160 blocks
[root@server ~]# resize2fs /dev/vg0/lv0 8G ##縮減文件系統大小至8G
resize2fs 1.42.9 (28-Dec-2013)
Resizing the filesystem on /dev/vg0/lv0 to 2097152 (4k) blocks.
The filesystem on /dev/vg0/lv0 is now 2097152 blocks long.
[root@server ~]# mount /dev/vg0/lv0 /mnt/ ##重新掛載
[root@server ~]# lvreduce -L 8G /dev/vg0/lv0 ##縮減lv0大小至8G
WARNING: Reducing active logical volume to 8.00 GiB
THIS MAY DESTROY YOUR DATA (filesystem etc.)
Do you really want to reduce lv0? [y/n]: y
Reducing logical volume lv0 to 8.00 GiB
Logical volume lv0 successfully resized
####監控內容####
Every 1.0s: pvs;vgs;lvs;df -h /mnt Wed May 9 10:11:15 2018
PV VG Fmt Attr PSize PFree
/dev/vdb1 vg0 lvm2 a-- 10.00g 2.00g
/dev/vdc1 vg0 lvm2 a-- 10.00g 10.00g
VG #PV #LV #SN Attr VSize VFree
vg0 2 1 0 wz--n- 19.99g 11.99g
LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert
lv0 vg0 -wi-ao---- 8.00g
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg0-lv0 7.8G 37M 7.4G 1% /mnt
####如果我們需要移除/dev/vdb1,但是/dev/vdb1上面有數據，我們需要遷移數據至/dev/vdc1
[root@server ~]# pvmove /dev/vdb1 /dev/vdc1 ##遷移vdb1的數據至vdc1
/dev/vdb1: Moved: 0.4%
/dev/vdb1: Moved: 100.0%
[root@server ~]# vgreduce vg0 /dev/vdb1 ##從vg0中移除/dev/vdb1
Removed "/dev/vdb1" from volume group "vg0"
[root@server ~]# pvremove /dev/vdb1 ##從pv中移除/dev/vdb1
Labels on physical volume "/dev/vdb1" successfully wiped
####監控內容####
Every 1.0s: pvs;vgs;lvs;df -h /mnt Wed May 9 10:18:22 2018
PV VG Fmt Attr PSize PFree
/dev/vdc1 vg0 lvm2 a-- 10.00g 2.00g
VG #PV #LV #SN Attr VSize VFree
vg0 1 1 0 wz--n- 10.00g 2.00g
LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert
lv0 vg0 -wi-ao---- 8.00g
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg0-lv0 7.8G 37M 7.4G 1% /mnt
LVM快照
###將vdb1重新添加至vg0###
[root@server ~]# pvcreate /dev/vdb1
Physical volume "/dev/vdb1" successfully created
[root@server ~]# vgextend vg0 /dev/vdb1
Volume group "vg0" successfully extended
[root@server ~]# touch /mnt/file{1..7} ##創建測試文件
[root@server ~]# ls /mnt
file1 file2 file3 file4 file5 file6 file7 lost+found
[root@server ~]# umount /dev/vg0/lv0 ##解除掛載
###創建快照###
[root@server ~]# lvcreate -L 2G -n lvbak -s /dev/vg0/lv0 ##創建一個2G大小的快照，名稱lvbak
Logical volume "lvbak" created
[root@server ~]# mount /dev/vg0/lvbak /mnt ##掛載快照
[root@server ~]# ls /mnt ##查看測試文件
file1 file2 file3 file4 file5 file6 file7 lost+found
[root@server ~]# rm -rf /mnt/* ##刪除測試文件
[root@server ~]# ls /mnt
[root@server ~]# umount /mnt ##解除掛載
[root@server ~]# lvremove /dev/vg0/lvbak ##刪除快照
Do you really want to remove active logical volume lvbak? [y/n]: y
Logical volume "lvbak" successfully removed
[root@server ~]# lvcreate -L 2G -n lvbak -s /dev/vg0/lv0 ##重新創建快照
Logical volume "lvbak" created
[root@server ~]# mount /dev/vg0/lvbak /mnt ##掛載
[root@server ~]# ls /mnt ##查看
file1 file2 file3 file4 file5 file6 file7 lost+found
####監控內容####
Every 1.0s: pvs;vgs;lvs;df -h /mnt Wed May 9 10:35:16 2018
PV VG Fmt Attr PSize PFree
/dev/vdb1 vg0 lvm2 a-- 10.00g 8.00g
/dev/vdc1 vg0 lvm2 a-- 10.00g 2.00g
VG #PV #LV #SN Attr VSize VFree
vg0 2 2 1 wz--n- 19.99g 9.99g
LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert
lv0 vg0 owi-a-s--- 8.00g
lvbak vg0 swi-aos--- 2.00g lv0 0.00
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg0-lvbak 7.8G 37M 7.4G 1% /mnt
####創建快照設備的數據被更改，重新建立快照就可恢復數據####
磁盤配額
[root@server ~]# umount /dev/vg0/lvbak
[root@server ~]# mount -o usrquota,grpquota /dev/vg0/lvbak /mnt ##重新掛載激活配額功能參數
[root@server ~]# quotaon -ug /dev/vg0/lvba ##開啓配額
[root@server ~]# edquota -u student ##編輯student用戶的配額
isk quotas for user student (uid 1000):
Filesystem blocks soft hard inodes soft hard
/dev/mapper/vg0-lvbak 0 0 20M 0 0 0
[root@server ~]# su - student ##切換到student用戶
Last login: Wed May 9 10:57:10 EDT 2018 on pts/0
[student@server ~]$ dd if=/dev/zero of=/mnt/studentfile bs=1M count=10 ##創建一個10M大小的測試文件
10+0 records in
10+0 records out
10485760 bytes (10 MB) copied, 0.00391326 s, 2.7 GB/s
[student@server ~]$ ls -hl /mnt/studentfile ##查看文件
-rw-rw-r--. 1 student student 10M May 9 10:59 /mnt/studentfile
[student@server ~]$ dd if=/dev/zero of=/mnt/studentfile bs=1M count=30 ##創建一個30M大小的測試文件
dm-1: write failed, user block limit reached.
dd: error writing ‘/mnt/studentfile’: Disk quota exceeded
21+0 records in
20+0 records out
20971520 bytes (21 MB) copied, 0.029637 s, 708 MB/s
[student@server ~]$ ls -lh /mnt/studentfile
-rw-rw-r--. 1 student student 20M May 9 11:03 /mnt/studentfile ##配額20M，配額生效
###開機自動激活配額###
vim /etc/fstab
/dev/vg0/lvbak /mnt ext4 defaults,usrquota,grpquota 0 0
###關閉配額###
刪除/etc/fstab中的配額參數
[root@server ~]# quotaoff -ugv /dev/vg0/lvbak ##關閉配額功能
/dev/mapper/vg0-lvbak [/mnt]: group quotas turned off
/dev/mapper/vg0-lvbak [/mnt]: user quotas turned off
刪除LVM
[root@server ~]# umount /mnt ##解除掛載
[root@server ~]# lvremove /dev/vg0/lvbak ##刪除lvbak
Do you really want to remove active logical volume lvbak? [y/n]: y
Logical volume "lvbak" successfully removed
[root@server ~]# lvremove /dev/vg0/lv0 ##刪除lv0
Do you really want to remove active logical volume lv0? [y/n]: y
Logical volume "lv0" successfully removed
[root@server ~]# vgremove vg0 ##刪除vg0
Volume group "vg0" successfully removed
[root@server ~]# pvremove /dev/vd{b,c}1 ##刪除pv，/dev/vdb1和/dev/vdc1
Labels on physical volume "/dev/vdb1" successfully wiped
Labels on physical volume "/dev/vdc1" successfully wiped
###監控內容###
Every 1.0s: pvs;vgs;lvs;df -h /mnt Wed May 9 11:13:54 2018
No volume groups found
No volume groups found
Filesystem Size Used Avail Use% Mounted on
/dev/vda1 10G 3.0G 7.1G 30% /
到此測試環境清理完畢，記得清理/etc/fstab中配置的自動掛載，否則開機時可能會出現錯誤。