创建、管理LVM：
创建分区
Disk /dev/xvdc: 2147 MB, 2147483648 bytes 255 heads, 63 sectors/track, 261 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xd199e24a Device Boot Start End Blocks Id System /dev/xvdc1 1 65 522081 8e Linux LVM #调整分区类型为 Linux LVM /dev/xvdc2 66 104 313267+ 8e Linux LVM /dev/xvdc3 105 181 618502+ 8e Linux LVM
创建PV：
pvcreate /path/to/device 创建物理卷
[root@VM_168_102_centos ~]# pvcreate /dev/xvdc{1,2,3}
Writing physical volume data to disk "/dev/xvdc1"
Physical volume "/dev/xvdc1" successfully created
Writing physical volume data to disk "/dev/xvdc2"
Physical volume "/dev/xvdc2" successfully created
Writing physical volume data to disk "/dev/xvdc3"
Physical volume "/dev/xvdc3" successfully createdpvs [ /path/to/pv_device ] 查看现有物理卷
[root@VM_168_102_centos ~]# pvs PV VG Fmt Attr PSize PFree /dev/xvdc1 lvm2 a-- 509.84m 509.84m /dev/xvdc2 lvm2 a-- 305.93m 305.93m /dev/xvdc3 lvm2 a-- 604.01m 604.01m [root@VM_168_102_centos ~]# pvs /dev/xvdc1 PV VG Fmt Attr PSize PFree /dev/xvdc1 lvm2 a-- 509.84m 509.84m
pvdisplay [ /path/to/pv_device ] 显示物理卷属性
[root@VM_168_102_centos ~]# pvdisplay /dev/xvdc1 "/dev/xvdc1" is a new physical volume of "509.84 MiB" --- NEW Physical volume --- PV Name /dev/xvdc1 #pv名字 VG Name #所属VG组 PV Size 509.84 MiB #PV大小 Allocatable NO PE Size 0 #pe大小，默认4 Total PE 0 #pe总计数量 Free PE 0 #空闲pe数量 Allocated PE 0 #被分配的PE数量 PV UUID sCID3E-GNNl-DoeW-BaLW-kuYj-fskV-RhLx8g
创建VG卷组：
vgcreate [-s SIZE] vg_name /path/to/pv_device
-s：指定PE大小，默认4MB
[root@VM_168_102_centos ~]# vgcreate -s 8 myvg /dev/xvdc{1,2}
Volume group "myvg" successfully createdvgs [ /path/to/vg_device ] 查看现有卷组
[root@VM_168_102_centos ~]# vgs
VG #PV #LV #SN Attr VSize VFree
myvg 2 0 0 wz--n- 808.00m 808.00mvgdisplay [ /path/to/vg_device ] 查看卷组属性
[root@VM_168_102_centos ~]# 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 808.00 MiB PE Size 8.00 MiB Total PE 101 Alloc PE / Size 0 / 0 Free PE / Size 101 / 808.00 MiB VG UUID R35yt2-S4dp-M9oY-4O1d-1CqX-4CQd-t0TpB9
vgrename vg_name new_name 修改卷组名称
[root@VM_168_102_centos ~]# vgrename myvg testvg Volume group "myvg" successfully renamed to "testvg" [root@VM_168_102_centos ~]# vgs VG #PV #LV #SN Attr VSize VFree testvg 2 0 0 wz--n- 808.00m 808.00m
创建逻辑卷：
lvcreate –L size –n name vg_name 创建逻辑卷
[root@VM_168_102_centos ~]# lvcreate -L 500M -n mylv /dev/myvg Rounding up size to full physical extent 504.00 MiB Logical volume "mylv" created
lvs [ /path/to/lv_device ] 查看现有逻辑卷
[root@VM_168_102_centos ~]# lvs LV VG Attr LSize Pool Origin Data% Move Log Copy% Convert mylv myvg -wi-a--- 504.00m
lvdisplay [ /path/to/lv_device ] 查看逻辑卷属性
/path/to/lv_device[root@VM_168_102_centos ~]# lvdisplay --- Logical volume --- LV Path /dev/myvg/mylv LV Name mylv VG Name myvg LV UUID nnelF1-sSxC-0A1l-IzLf-YqwL-djsy-lMeiTH LV Write Access read/write LV Creation host, time VM_168_102_centos, 2014-08-24 16:12:08 +0800 LV Status available # open 0 LV Size 504.00 MiB Current LE 63 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:7
讲mylv2逻辑据进行格式化挂载：
[root@VM_168_102_centos ~]# mke2fs -t ext4 /dev/myvg/mylv mke2fs 1.41.12 (17-May-2010) ...省略 This filesystem will be automatically checked every 26 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override. [root@VM_168_102_centos ~]# mount /dev/myvg/mylv /tmp/wanghan [root@VM_168_102_centos ~]# mount /dev/xvda1 on / type ext3 (rw,noatime,acl,user_xattr) proc on /proc type proc (rw) sysfs on /sys type sysfs (rw) devpts on /dev/pts type devpts (rw,mode=0620,gid=5) none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw) /dev/mapper/myvg-mylv on /tmp/wanghan type ext4 (rw)
将myvg剩余的空间分配200M给mylv2：
[root@VM_168_102_centos ~]# lvcreate -L 200M -n mylv2 /dev/myvg Logical volume "mylv2" created [root@VM_168_102_centos ~]# lvs LV VG Attr LSize Pool Origin Data% Move Log Copy% Convert mylv myvg -wi-a--- 504.00m mylv2 myvg -wi-a--- 200.00m [root@VM_168_102_centos ~]# vgs VG #PV #LV #SN Attr VSize VFree myvg 2 2 0 wz--n- 808.00m 104.00m
移除mylv2逻辑卷：
lvremove [ /path/to/lv_device ] 移除指定逻辑卷
[root@VM_168_102_centos ~]# lvremove /dev/myvg/mylv2 Do you really want to remove active logical volume mylv2? [y/n]: y Logical volume "mylv2" successfully removed [root@VM_168_102_centos ~]# lvs LV VG Attr LSize Pool Origin Data% Move Log Copy% Convert mylv myvg -wi-a--- 504.00m
扩展卷组：
准备好要添加的物理卷
[root@VM_168_102_centos ~]# pvs PV VG Fmt Attr PSize PFree /dev/xvdc1 myvg lvm2 a-- 504.00m 0 /dev/xvdc2 myvg lvm2 a-- 304.00m 304.00m /dev/xvdc3 lvm2 a-- 604.01m 604.01m
向卷组中添加物理卷
vgextend vg_name /path/to/pv_device
[root@VM_168_102_centos ~]# vgextend /dev/myvg /dev/xvdc3 Volume group "myvg" successfully extended [root@VM_168_102_centos ~]# vgs VG #PV #LV #SN Attr VSize VFree myvg 3 1 0 wz--n- 1.38g 904.00m [root@VM_168_102_centos ~]# pvs PV VG Fmt Attr PSize PFree /dev/xvdc1 myvg lvm2 a-- 504.00m 0 /dev/xvdc2 myvg lvm2 a-- 304.00m 304.00m /dev/xvdc3 myvg lvm2 a-- 600.00m 600.00m
缩减卷组
1、要移除的物理卷的总空间大小，要小于当前VG可用空间的大小
2、将要移除的PV上的数据移动至其他pv
pvmove 可以将一个PV上的数据迁移到新的PV上
[root@VM_168_102_centos ~]# pvmove /dev/xvdc2 No data to move for myvg
3、将要指定的PV从VG中移除
vgreduce 从卷组中删除物理卷
[root@VM_168_102_centos ~]# vgreduce /dev/myvg /dev/xvdc2 Removed "/dev/xvdc2" from volume group "myvg" [root@VM_168_102_centos ~]# pvs PV VG Fmt Attr PSize PFree /dev/xvdc1 myvg lvm2 a-- 504.00m 0 /dev/xvdc2 lvm2 a-- 305.93m 305.93m /dev/xvdc3 myvg lvm2 a-- 600.00m 600.00m [root@VM_168_102_centos ~]# vgs VG #PV #LV #SN Attr VSize VFree myvg 2 1 0 wz--n- 1.08g 600.00m
扩展逻辑卷：
1、确定要扩展的逻辑卷所属的卷组有足够的剩余空间
2、扩展物理边界(物理边界：我们对一个磁盘进行分区的分区边界)
lvextend 扩展逻辑卷空间
[root@VM_168_102_centos ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/xvda1 7.9G 2.2G 5.3G 30% / /dev/mapper/myvg-mylv 489M 31M 433M 7% /tmp/wanghan [root@VM_168_102_centos ~]# lvextend -L 700M /dev/myvg/mylv Rounding size to boundary between physical extents: 704.00 MiB Extending logical volume mylv to 704.00 MiB Logical volume mylv successfully resized [root@VM_168_102_centos ~]# df -lh Filesystem Size Used Avail Use% Mounted on /dev/xvda1 7.9G 2.2G 5.3G 30% / /dev/mapper/myvg-mylv 489M 31M 433M 7% /tmp/wanghan
3、扩展逻辑边界（逻辑边界:我们格式化分区，建立文件系统后形成的分区边界）
resize2fs：文件系统大小调整工具
[root@VM_168_102_centos ~]# resize2fs /dev/myvg/mylv resize2fs 1.41.12 (17-May-2010) Filesystem at /dev/myvg/mylv is mounted on /tmp/wanghan; on-line resizing required old desc_blocks = 2, new_desc_blocks = 3 Performing an on-line resize of /dev/myvg/mylv to 720896 (1k) blocks. The filesystem on /dev/myvg/mylv is now 720896 blocks long. [root@VM_168_102_centos ~]# df -lh Filesystem Size Used Avail Use% Mounted on /dev/xvda1 7.9G 2.2G 5.3G 30% / /dev/mapper/myvg-mylv 682M 31M 616M 5% /tmp/wanghan [root@VM_168_102_centos ~]# lvs LV VG Attr LSize Pool Origin Data% Move Log Copy% Convert mylv myvg -wi-ao-- 704.00m
缩减逻辑卷（有风险，不推荐）：
1、卸载卷，并执行强制检测
[root@VM_168_102_centos ~]# umount /dev/myvg/mylv [root@VM_168_102_centos ~]# e2fsck -f /dev/myvg/mylv e2fsck 1.41.12 (17-May-2010) 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/myvg/mylv: 1307/180224 files (0.2% non-contiguous), 54323/720896 blocks
2、先缩减逻辑边界
[root@VM_168_102_centos ~]# resize2fs /dev/myvg/mylv 400M resize2fs 1.41.12 (17-May-2010) Resizing the filesystem on /dev/myvg/mylv to 409600 (1k) blocks. The filesystem on /dev/myvg/mylv is now 409600 blocks long.
3、再缩减物理边界
[root@VM_168_102_centos ~]# lvreduce -L 400M /dev/myvg/mylv WARNING: Reducing active logical volume to 400.00 MiB THIS MAY DESTROY YOUR DATA (filesystem etc.) Do you really want to reduce mylv? [y/n]: y Reducing logical volume mylv to 400.00 MiB Logical volume mylv successfully resized [root@VM_168_102_centos ~]# lvs LV VG Attr LSize Pool Origin Data% Move Log Copy% Convert mylv myvg -wi-a--- 400.00m
快照卷：
1、生命周期为整个数据时长，在这段时长内，数据的增长量不能超出快照卷大小 2、快照卷应该是只读的 3、跟原卷在同一卷组内
[root@VM_168_102_centos ~]# lvcreate -s -L 50M -n snap-mylv -p r /dev/myvg/mylv Rounding up size to full physical extent 56.00 MiB Logical volume "snap-mylv" created [root@VM_168_102_centos ~]# lvs LV VG Attr LSize Pool Origin Data% Move Log Copy% Convert mylv myvg owi-a-s- 400.00m snap-mylv myvg sri-a-s- 56.00m mylv 0.00
原文地址：http://putongren.blog.51cto.com/9086263/1544165
