LVM
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。
结构
最下面的一层是3 Physical Volume PV(物理卷)
上一层 2 Volume Group VG (卷组) 逻辑存储小匣子：PE:Physical Extend,盘区
最上面一层 1 Logical Volume (逻辑卷) LV
命令介绍
PV
pvcreate:创建模式
pvs :查看pv信息
pvdisplay:查看pv的详细信息
pvscan ：扫描pv信息
pvremove ：删除
pvmove :移动
VG
vgcreate VG_NAME /PATH/TO/PV
-S #：PE大小，默认为4MB
vgextend 拓展
vgreduce 减少
vgremove 删除
vgdisplay
vgs
LV
lvcreate
-n LV_NEME -L #G(大小)
lvremove
lvextend
lvreduce
lvs
lvdisplay
新建7G ,3G,5G逻辑卷到时候实验用
[root@localhost ~]# fdisk /dev/sda
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
Command (m for help): p
Disk /dev/sda: 48.3 GB, 48318382080 bytes
64 heads, 32 sectors/track, 46080 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0005361c
Device Boot Start End Blocks Id System
/dev/sda1 * 2 201 204800 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 202 10201 10240000 83 Linux
Partition 2 does not end on cylinder boundary.
/dev/sda3 10202 12201 2048000 82 Linux swap / Solaris
Partition 3 does not end on cylinder boundary.
/dev/sda4 12202 46080 34692096 5 Extended
Partition 4 does not end on cylinder boundary.
/dev/sda5 12204 14203 2048000 6 FAT16
/dev/sda6 14204 15228 1049584 fd Linux raid autodetect
/dev/sda7 15229 16253 1049584 fd Linux raid autodetect
/dev/sda8 16254 17278 1049584 fd Linux raid autodetect
/dev/sda9 17279 18303 1049584 fd Linux raid autodetect
/dev/sda10 18304 19328 1049584 fd Linux raid autodetect
Command (m for help): n
First cylinder (12202-46080, default 12202): 19329
Last cylinder, +cylinders or +size{K,M,G} (19329-46080, default 46080): +7G
Command (m for help): p
Disk /dev/sda: 48.3 GB, 48318382080 bytes
64 heads, 32 sectors/track, 46080 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0005361c
Device Boot Start End Blocks Id System
/dev/sda1 * 2 201 204800 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 202 10201 10240000 83 Linux
Partition 2 does not end on cylinder boundary.
/dev/sda3 10202 12201 2048000 82 Linux swap / Solaris
Partition 3 does not end on cylinder boundary.
/dev/sda4 12202 46080 34692096 5 Extended
Partition 4 does not end on cylinder boundary.
/dev/sda5 12204 14203 2048000 6 FAT16
/dev/sda6 14204 15228 1049584 fd Linux raid autodetect
/dev/sda7 15229 16253 1049584 fd Linux raid autodetect
/dev/sda8 16254 17278 1049584 fd Linux raid autodetect
/dev/sda9 17279 18303 1049584 fd Linux raid autodetect
/dev/sda10 18304 19328 1049584 fd Linux raid autodetect
/dev/sda11 19329 26497 7341040 83 Linux
Command (m for help): n
First cylinder (12202-46080, default 12202): 26498
Last cylinder, +cylinders or +size{K,M,G} (26498-46080, default 46080): +3G
Command (m for help): p
Disk /dev/sda: 48.3 GB, 48318382080 bytes
64 heads, 32 sectors/track, 46080 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0005361c
Device Boot Start End Blocks Id System
/dev/sda1 * 2 201 204800 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 202 10201 10240000 83 Linux
Partition 2 does not end on cylinder boundary.
/dev/sda3 10202 12201 2048000 82 Linux swap / Solaris
Partition 3 does not end on cylinder boundary.
/dev/sda4 12202 46080 34692096 5 Extended
Partition 4 does not end on cylinder boundary.
/dev/sda5 12204 14203 2048000 6 FAT16
/dev/sda6 14204 15228 1049584 fd Linux raid autodetect
/dev/sda7 15229 16253 1049584 fd Linux raid autodetect
/dev/sda8 16254 17278 1049584 fd Linux raid autodetect
/dev/sda9 17279 18303 1049584 fd Linux raid autodetect
/dev/sda10 18304 19328 1049584 fd Linux raid autodetect
/dev/sda11 19329 26497 7341040 83 Linux
/dev/sda12 26498 29570 3146736 83 Linux
Command (m for help): n
First cylinder (12202-46080, default 12202): 29571
Last cylinder, +cylinders or +size{K,M,G} (29571-46080, default 46080): +5G
Command (m for help): t
Partition number (1-13): 11
Hex code (type L to list codes): L
0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris
1 FAT12 39 Plan 9 82 Linux swap / So c1 DRDOS/sec (FAT-
2 XENIX root 3c PartitionMagic 83 Linux c4 DRDOS/sec (FAT-
3 XENIX usr 40 Venix 80286 84 OS/2 hidden C: c6 DRDOS/sec (FAT-
4 FAT16 <32M 41 PPC PReP Boot 85 Linux extended c7 Syrinx
5 Extended 42 SFS 86 NTFS volume set da Non-FS data
6 FAT16 4d QNX4.x 87 NTFS volume set db CP/M / CTOS / .
7 HPFS/NTFS 4e QNX4.x 2nd part 88 Linux plaintext de Dell Utility
8 AIX 4f QNX4.x 3rd part 8e Linux LVM df BootIt
9 AIX bootable 50 OnTrack DM 93 Amoeba e1 DOS access
a OS/2 Boot Manag 51 OnTrack DM6 Aux 94 Amoeba BBT e3 DOS R/O
b W95 FAT32 52 CP/M 9f BSD/OS e4 SpeedStor
c W95 FAT32 (LBA) 53 OnTrack DM6 Aux a0 IBM Thinkpad hi eb BeOS fs
e W95 FAT16 (LBA) 54 OnTrackDM6 a5 FreeBSD ee GPT
f W95 Ext'd (LBA) 55 EZ-Drive a6 OpenBSD ef EFI (FAT-12/16/
10 OPUS 56 Golden Bow a7 NeXTSTEP f0 Linux/PA-RISC b
11 Hidden FAT12 5c Priam Edisk a8 Darwin UFS f1 SpeedStor
12 Compaq diagnost 61 SpeedStor a9 NetBSD f4 SpeedStor
14 Hidden FAT16 <3 63 GNU HURD or Sys ab Darwin boot f2 DOS secondary
16 Hidden FAT16 64 Novell Netware af HFS / HFS+ fb VMware VMFS
17 Hidden HPFS/NTF 65 Novell Netware b7 BSDI fs fc VMware VMKCORE
18 AST SmartSleep 70 DiskSecure Mult b8 BSDI swap fd Linux raid auto
1b Hidden W95 FAT3 75 PC/IX bb Boot Wizard hid fe LANstep
1c Hidden W95 FAT3 80 Old Minix be Solaris boot ff BBT
1e Hidden W95 FAT1
Hex code (type L to list codes): 8e
Changed system type of partition 11 to 8e (Linux LVM)
Command (m for help): t
Partition number (1-13): 12
Hex code (type L to list codes): 8e
Changed system type of partition 12 to 8e (Linux LVM)
最后保存
[root@localhost ~]# fdisk -l
Disk /dev/sda: 48.3 GB, 48318382080 bytes
64 heads, 32 sectors/track, 46080 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0005361c
Device Boot Start End Blocks Id System
/dev/sda1 * 2 201 204800 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 202 10201 10240000 83 Linux
Partition 2 does not end on cylinder boundary.
/dev/sda3 10202 12201 2048000 82 Linux swap / Solaris
Partition 3 does not end on cylinder boundary.
/dev/sda4 12202 46080 34692096 5 Extended
Partition 4 does not end on cylinder boundary.
/dev/sda5 12204 14203 2048000 6 FAT16
/dev/sda6 14204 15228 1049584 fd Linux raid autodetect
/dev/sda7 15229 16253 1049584 fd Linux raid autodetect
/dev/sda8 16254 17278 1049584 fd Linux raid autodetect
/dev/sda9 17279 18303 1049584 fd Linux raid autodetect
/dev/sda10 18304 19328 1049584 fd Linux raid autodetect
/dev/sda11 19329 26497 7341040 8e Linux LVM
/dev/sda12 26498 29570 3146736 8e Linux LVM
/dev/sda13 29571 34691 5243888 8e Linux LVM
Disk /dev/md127: 2146 MB, 2146435072 bytes
2 heads, 4 sectors/track, 524032 cylinders
Units = cylinders of 8 * 512 = 4096 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 524288 bytes / 1048576 bytes
Disk identifier: 0x00000000
Disk /dev/md1: 1073 MB, 1073676288 bytes
2 heads, 4 sectors/track, 262128 cylinders
Units = cylinders of 8 * 512 = 4096 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
[root@localhost ~]# pvcreate /dev/sda{11,12}
Physical volume "/dev/sda11" successfully created
Physical volume "/dev/sda12" successfully created
[root@localhost ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda11 lvm2 --- 7.00g 7.00g
/dev/sda12 lvm2 --- 3.00g 3.00g
[root@localhost ~]# pvsdisplay
-bash: pvsdisplay: command not found
[root@localhost ~]# pvdisplay
"/dev/sda11" is a new physical volume of "7.00 GiB"
--- NEW Physical volume ---
PV Name /dev/sda11
VG Name
PV Size 7.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID du3bb3-lMzi-QlLP-TnBA-lFT6-KAeq-ILZ2TA
"/dev/sda12" is a new physical volume of "3.00 GiB"
--- NEW Physical volume ---
PV Name /dev/sda12
VG Name
PV Size 3.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID vAcdQ6-xItu-mGWW-ky4t-TRrF-LXPe-cfGQm2
[root@localhost ~]# pvscan
PV /dev/sda11 lvm2 [7.00 GiB]
PV /dev/sda12 lvm2 [3.00 GiB]
Total: 2 [10.00 GiB] / in use: 0 [0 ] / in no VG: 2 [10.00 GiB]
建立卷组
[root@localhost ~]# vgcreate myvg /dev/sda{11,12}
Volume group "myvg" successfully created
[root@localhost ~]# vgs
VG #PV #LV #SN Attr VSize VFree
myvg 2 0 0 wz--n- 9.99g 9.99g
[root@localhost ~]# vgdisplay
--- Volume group ---
VG Name myvg
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 1
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 0
Open LV 0
Max PV 0
Cur PV 2
Act PV 2
VG Size 9.99 GiB
PE Size 4.00 MiB
Total PE 2558
Alloc PE / Size 0 / 0
Free PE / Size 2558 / 9.99 GiB
VG UUID WmyW7f-raGk-fOoF-Bmt5-SEeA-yJVz-DNpilW
减少增加卷组
减少
[root@localhost ~]# pvmove /dev/sda12
No data to move for myvg
[root@localhost ~]# vgreduce myvg /dev/sda12
Removed "/dev/sda12" from volume group "myvg"
[root@localhost ~]# vgs
VG #PV #LV #SN Attr VSize VFree
myvg 1 0 0 wz--n- 7.00g 7.00g
[root@localhost ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda11 myvg lvm2 a-- 7.00g 7.00g
/dev/sda12 lvm2 --- 3.00g 3.00g
添加
[root@localhost ~]# pvcreate /dev/sda13
Physical volume "/dev/sda13" successfully created
[root@localhost ~]# vgextend myvg /dev/sda13
Volume group "myvg" successfully extended
[root@localhost ~]# vgdisplay
--- Volume group ---
VG Name myvg
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 3
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 0
Open LV 0
Max PV 0
Cur PV 2
Act PV 2
VG Size 11.99 GiB
PE Size 4.00 MiB
Total PE 3070
Alloc PE / Size 0 / 0
Free PE / Size 3070 / 11.99 GiB
VG UUID WmyW7f-raGk-fOoF-Bmt5-SEeA-yJVz-DNpilW
[root@localhost ~]# vgs
VG #PV #LV #SN Attr VSize VFree
myvg 2 0 0 wz--n- 11.99g 11.99g
添加逻辑卷
[root@localhost ~]# lvcreate -L 50M -n testlv myvg
Rounding up size to full physical extent 52.00 MiB
Logical volume "testlv" created.
[root@localhost ~]# mke2fs -t ext4 /dev/myvg/testlv
mke2fs 1.41.12 (17-May-2010)
文件系统标签=
操作系统:Linux
块大小=1024 (log=0)
分块大小=1024 (log=0)
Stride=0 blocks, Stripe width=0 blocks
13328 inodes, 53248 blocks
2662 blocks (5.00%) reserved for the super user
第一个数据块=1
Maximum filesystem blocks=54525952
7 block groups
8192 blocks per group, 8192 fragments per group
1904 inodes per group
Superblock backups stored on blocks:
8193, 24577, 40961
正在写入inode表: 完成
Creating journal (4096 blocks): 完成
Writing superblocks and filesystem accounting information: 完成
This filesystem will be automatically checked every 32 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
[root@localhost ~]# mount /dev/myvg/testlv /mnt
[root@localhost ~]# lvs
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
testlv myvg -wi-ao---- 52.00m
拓展逻辑卷
[root@localhost ~]# vgs
VG #PV #LV #SN Attr VSize VFree
myvg 2 1 0 wz--n- 11.99g 11.94g
[root@localhost ~]# lvextend -L 5G /dev/myvg/testlv
Size of logical volume myvg/testlv changed from 52.00 MiB (13 extents) to 5.00 GiB (1280 extents).
Logical volume testlv successfully resized
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 9.5G 3.8G 5.3G 42% /
tmpfs 940M 72K 940M 1% /dev/shm
/dev/sda1 190M 40M 140M 23% /boot
/dev/sda5 1.9G 3.0M 1.8G 1% /opt
/dev/mapper/myvg-testlv
47M 842K 43M 2% /mnt
[root@localhost ~]# lvs
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
testlv myvg -wi-ao---- 5.00g
然后再拓展文件系统
[root@localhost ~]# resize2fs -p /dev/myvg/testlv
resize2fs 1.41.12 (17-May-2010)
Filesystem at /dev/myvg/testlv is mounted on /mnt; on-line resizing required
old desc_blocks = 1, new_desc_blocks = 20
Performing an on-line resize of /dev/myvg/testlv to 5242880 (1k) blocks.
The filesystem on /dev/myvg/testlv is now 5242880 blocks long.
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 9.5G 3.8G 5.3G 42% /
tmpfs 940M 72K 940M 1% /dev/shm
/dev/sda1 190M 40M 140M 23% /boot
/dev/sda5 1.9G 3.0M 1.8G 1% /opt
/dev/mapper/myvg-testlv
4.9G 2.6M 4.6G 1% /mnt
缩减逻辑卷
注意:1,得先卸载；
2,确保缩减后的空间大小依然能存储原有的所有数据
3,在缩减之前应该先强行检查文件，以确保文件系统处于一致性状态
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 9.5G 3.8G 5.3G 42% /
tmpfs 940M 72K 940M 1% /dev/shm
/dev/sda1 190M 40M 140M 23% /boot
/dev/sda5 1.9G 3.0M 1.8G 1% /opt
/dev/mapper/myvg-testlv
4.9G 2.6M 4.6G 1% /mnt
[root@localhost ~]# mount /mnt
mount: /dev/mapper/myvg-testlv already mounted or /mnt busy
mount: according to mtab, /dev/mapper/myvg-testlv is already mounted on /mnt
[root@localhost ~]# umount /mnt
[root@localhost ~]# e2fsck -f /dev/myvg/testlv
e2fsck 1.41.12 (17-May-2010)
第一步: 检查inode,块,和大小
第二步: 检查目录结构
第3步: 检查目录连接性
Pass 4: Checking reference counts
第5步: 检查簇概要信息
/dev/myvg/testlv: 11/1218560 files (9.1% non-contiguous), 160637/5242880 blocks
[root@localhost ~]# resize2fs /dev/myvg/testlv 3G
resize2fs 1.41.12 (17-May-2010)
Resizing the filesystem on /dev/myvg/testlv to 3145728 (1k) blocks.
The filesystem on /dev/myvg/testlv is now 3145728 blocks long.
[root@localhost ~]# lvreduce -L 3G /dev/myvg/testlv
WARNING: Reducing active logical volume to 3.00 GiB
THIS MAY DESTROY YOUR DATA (filesystem etc.)
Do you really want to reduce testlv? [y/n]: y
Size of logical volume myvg/testlv changed from 5.00 GiB (1280 extents) to 3.00 GiB (768 extents).
Logical volume testlv successfully resized
[root@localhost ~]# mount /dev/myvg/testlv /mnt
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 9.5G 3.8G 5.3G 42% /
tmpfs 940M 72K 940M 1% /dev/shm
/dev/sda1 190M 40M 140M 23% /boot
/dev/sda5 1.9G 3.0M 1.8G 1% /opt
/dev/mapper/myvg-testlv
3.0G 2.6M 2.8G 1% /mnt