LVM Management under Linux

1. Experimental environment:

1), Centos6.5-32bit;

Four SCSI hard drives, respectively:

/dev/sdb (10G),/DEV/SDC (5G),/DEV/SDD (15G),/DEV/SDE (20G);

Requirements Package: LVM2

2. Experimental steps:

1), install the required packages

Yum--disablerepo=\*--enablerepo=c6-media Install lvm2 mdadm-y

2), create a physical volume

[Email protected] ~]# PVCREATE/DEV/SDB/DEV/SDC/DEV/SDD physical Volume "/DEV/SDB" successfully created physical Volu Me "/DEV/SDC" successfully created physical volume "/DEV/SDD" successfully created

To display the created physical volume

[[email protected] ~]# pvdisplay    "/dev/sdb"  is a new  physical volume of  "10.00 gib"   --- NEW Physical volume ---   PV Name                /dev/sdb            #物理卷名称   vg name                                     #加入的存储池名称   PV Size                10.00 GiB           #物理卷的大小   allocatable            NO                    pe size                0     Total PE               0  Free PE                0  Allocated PE           0  PV UUID                lqridi-ms2t-jq0y-l137-e9dd-hsdd-xabiby

Scan physical volumes on the system

[Email protected] ~]# pvscan pv/dev/sdb lvm2 [10.00 GiB] PV/DEV/SDC lvm2 [  5.00 GiB] PV/DEV/SDD lvm2 [15.00 Gib] total:3 [30.00 GIB]/in use:0 [0]/In no vg:3 [30.00 GiB]

3), create volume group (storage pool)

[Email protected] ~]# vgcreate FCY-VG/DEV/SDB/DEV/SDC Volume Group "FCY-VG" successfully created

Show Volume Group

[[email protected] ~]# vgdisplay   --- Volume group ---   VG Name                fcy-vg           #卷组名称   System ID                Format                 lvm2              #卷组格式   Metadata Areas         2  Metadata Sequence No  1  VG Access              read/write        #卷组权限   VG Status              resizable        #卷组状态 (expandable)   MAX LV                 0  Cur LV                 0  Open LV                0  Max PV                 0  Cur PV                 2  act  pv                2   VG Size                14.99 GiB          #存储池大小   PE Size                4.00 mib            #PE块的大小   Total PE               3838                #总PE数量   alloc pe / size       0 /  0     Free  PE / Size        3838 / 14.99 GiB  VG UUID                aiezvv-y5gt-u7s1-9vcb-5yzp-qsmq-t7wo7n

Scan a volume group

[Email protected] ~]# Vgscan Reading all physical volumes.  This is a while ... Found Volume Group "FCY-VG" using metadata type LVM2

Adding physical volumes to a volume group

[Email protected] ~]# vgextend fcy-vg/dev/sde Physical Volume "/DEV/SDE" successfully created volume Group "FCY-VG" Su Ccessfully Extended

Remove a physical volume from a volume group

[Email protected] ~]# vgreduce fcy-vg/dev/sde removed "/DEV/SDE" from volume Group "FCY-VG"

Delete a volume group

Vgremove FCY-VG

4), creating a logical volume

[[email protected] ~]# lvcreate-l 10g-n fcy-lv fcy-vg #-l Specify size,-n Specify name Logical volume "FCY-LV" created

viewing logical volumes

[[email protected] ~]# lvdisplay   --- Logical volume ---   LV Path                 /dev/fcy-vg/fcy-lv  LV Name                 fcy-lv  VG Name                 fcy-vg  LV UUID                 kf3klx-2aex-c3el-eduy-a3p8-jh0g-w9ighq   lv write access        read/write  lv  creation host, time fcy.com.cn, 2015-07-15 20:05:27 +0800  lv  status              available   # open                 0   lv size                 10.00 gib  current le              2560  Segments                2  Allocation              inherit  read ahead sectors     auto  -  currently set to     256  Block device            253:0

Scan logical Volumes

[[email protected] ~]# lvscan ACTIVE '/dev/fcy-vg/fcy-lv ' [10.00 GiB] Inherit

To format a created logical volume

[[email protected] ~]# mkfs -t ext3 /dev/fcy-vg/fcy-lv mke2fs 1.41.12   (17-may-2010) filesystem label=os type: linuxblock size=4096  (log=2) Fragment  size=4096  (log=2) Stride=0 blocks, stripe width=0 blocks655360 inodes,  2621440 blocks131072 blocks  (5.00%)  reserved for the super  userfirst data block=0maximum filesystem blocks=268435456080 block groups32768  blocks per group, 32768 fragments per group8192 inodes per  groupsuperblock backups stored on blocks: 32768, 98304, 163840, 229376 , 294912, 819200, 884736, 1605632writing inode tables: done                              creating journal  (32768 blocks):  donewriting superblocks and  filesystem accounting information: doneThis filesystem will be  Automatically checked every 26 mounts or180 days, whichever comes  first.  use tune2fs -c or -i to override.

     mount logical volumes

[[email protected] ~]# mount /dev/fcy-vg/fcy-lv /mnt/fcy-lvm/[[email protected]  ~]# df -hFilesystem                    size  used avail use% mounted on/dev/ sda2                      15G  1.9G   12G  14% /tmpfs                          250m     0  250m   0% /dev/shm/dev/ sda1                     194M   26M  158M  15% /boot/dev/sr0                      3.6g  3.6g      0 100% /media/cdrom/dev/mapper/fcy--vg-fcy--lv  9.9G   151m  9.2g   2% /mnt/fcy-lvm    #已经挂载并可以使用

     expanding Logical volume size online

[[email protected] ~]# lvresize -l +1g /dev/fcy-vg/fcy-lv    Extending logical volume fcy-lv to 11.00 gib  logical volume  fcy-lv successfully resized[[email protected] ~]# lvdisplay   -- - logical volume ---  LV Path                 /dev/fcy-vg/fcy-lv  LV Name                 fcy-lv  vg name                 fcy-vg   LV UUID                 KF3klx-2aex-c3el-EduY-a3p8-Jh0G-W9IgHQ  LV Write Access         read/write  lv creation host, time fcy.com.cn, 2015-07-15 20:05:27 +0800   LV Status               available  # open                  1  LV Size                 11.00 GiB  Current LE              2816  Segments                2  Allocation              inherit  Read ahead sectors      auto  - currently set to     256   block device           253:0 

Note: After executing the lvresize, continue with the following command to extend the completion

[Email protected] ~]# resize2fs/dev/fcy-vg/fcy-lv resize2fs 1.41.12 (17-may-2010) Filesystem AT/DEV/FCY-VG/FCY-LV is mo Unted ON/MNT/FCY-LVM; On-line resizing Requiredold desc_blocks = 1, new_desc_blocks = 1Performing an on-line resize of/dev/fcy-vg/fcy-lv to 288 3584 (4k) blocks. The filesystem on/dev/fcy-vg/fcy-lv is now 2883584 blocks long.

Reduce the size of the logical volume ( Note that the directive does not support online, so uninstall the mount point first )

[Email protected] ~]# e2fsck-f/dev/fcy-vg/fcy-lv #强制系统文件检测e2fsck 1.41.12 (17-may-2010) Pass 1:checking inodes, block S, and Sizespass 2:checking directory structurepass 3:checking directory connectivitypass 4:checking reference Countspa SS 5:checking Group Summary information/dev/fcy-vg/fcy-lv:11/720896 files (0.0% non-contiguous), 84449/2883584 blocks

[[email protected] ~]# lvresize-l 8G/DEV/FCY-VG/FCY-LV warning:reducing Active Logical Volume to 8.00 GiB this may DE Stroy YOUR DATA (filesystem etc) Does really want to reduce fcy-lv? [y/n]: Y reducing Logical Volume FCY-LV to 8.00 GiB Logical volume FCY-LV successfully resized

Create a snapshot of a logical volume

[[email protected] ~]# lvcreate-l 1g-n fcy-snap-s/dev/fcy-vg/fcy-lv #-s Specifies the logical volume to take the snapshot Logical volume "Fcy-snap" created

Mount and compare

[[email protected] ~]# mount /dev/fcy-vg/fcy-snap /mnt/fcy-snapshot/[[email  protected] ~]# df -hfilesystem                      size  used avail use%  Mounted on/dev/sda2                        15G  1.9G   12G   14% /tmpfs                           250m     0   250M   0% /dev/shm/dev/sda1                       194m   26m   158m  15% /boot/dev/sr0                        3.6g  3.6g     0 100% / media/cdrom/dev/mapper/fcy--vg-fcy--lv    7.9g  151m  7.4g    2% /mnt/fcy-lvm/dev/mapper/fcy--vg-fcy--snap  7.9G  151M  7.4G    2% /mnt/fcy-snapshot

This article is from the "but evil Water Heart Pan" blog, please be sure to keep this source http://shmilyfl.blog.51cto.com/8897986/1675107

LVM Management under Linux