linux CentOS/redhat 6.5 LVM分区使用详解

1, 介绍

lvm是逻辑盘卷管理（logical volume manager）的简称，它是linux环境下对磁盘分区进行管理的一种机制，lvm是建立在硬盘和分区之上的一个逻辑层，来提高磁盘分 lvm
区管理的灵活性。前面谈到，lvm是在磁盘分区和文件系统之间添加的一个逻辑层，来为文件系统屏蔽下层磁盘分区布局，提供一个抽象的盘卷，在盘卷上建立文件系统。物理卷（physical volume）物理卷就是指硬盘分区或从逻辑上与磁盘分区具有同样功能的设备（如raid），是lvm的基本存储逻辑块，但和基本的物理存储介质（如分区、磁盘等）比较，却包含有与lvm相关的管理参数。

2，创建
[root@cn-iss-install-01 mapper]# fdisk -l
[root@cn-iss-install-01 mapper]# fdisk /dev/sdb
device contains neither a valid dos partition table, nor sun, sgi or osf disklabel
building a new dos disklabel with disk identifier 0x874c7742.
changes will remain in memory only, until you decide to write them.
after that, of course, the previous content won't be recoverable.
warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
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): m
command action
   a   toggle a bootable flag
   b   edit bsd disklabel
   c   toggle the dos compatibility flag
   d   delete a partition
   l   list known partition types
   m   print this menu
   n   add a new partition
   o   create a new empty dos partition table
   p   print the partition table
   q   quit without saving changes
   s   create a new empty sun disklabel
   t   change a partition's system id
   u   change display/entry units
   v   verify the partition table
   w   write table to disk and exit
   x   extra functionality (experts only)
command (m for help): p
disk /dev/sdb: 96.6 gb, 96636764160 bytes
255 heads, 63 sectors/track, 11748 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: 0x874c7742
   device boot      start         end      blocks   id system
command (m for help): n
command action
   e   extended
   p   primary partition (1-4)
p
partition number (1-4): 1
first cylinder (1-11748, default 1):
using default value 1
last cylinder, +cylinders or +size{k,m,g} (1-11748, default 11748): +80g
command (m for help): p
disk /dev/sdb: 96.6 gb, 96636764160 bytes
255 heads, 63 sectors/track, 11748 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: 0x874c7742
   device boot      start         end      blocks   id system
/dev/sdb1               1       10444    83891398+   5 extended
command (m for help): w
the partition table has been altered!
calling ioctl() to re-read partition table.
syncing disks.
[root@cn-iss-install-01 mapper]#reboot or
[root@cn-iss-install-01 packages]# partprobe
[root@cn-iss-install-01 ~]# fdisk -l
disk /dev/sda: 17.2 gb, 17179869184 bytes
64 heads, 32 sectors/track, 16384 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: 0x0005b1c0
   device boot      start         end      blocks   id system
/dev/sda1   *           2         251      256000   83 linux
partition 1 does not end on cylinder boundary.
/dev/sda2             252       16384    16520192   8e linux lvm
partition 2 does not end on cylinder boundary.
disk /dev/sdb: 96.6 gb, 96636764160 bytes
255 heads, 63 sectors/track, 11748 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: 0x874c7742
   device boot      start         end      blocks   id system
/dev/sdb1               1       10444    83891398+   5 extended
disk /dev/mapper/vg00-lv_rootfs: 16.4 gb, 16374562816 bytes
255 heads, 63 sectors/track, 1990 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: 0x00000000
disk /dev/mapper/vg00-lv_swap: 536 mb, 536870912 bytes
255 heads, 63 sectors/track, 65 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: 0x00000000
[root@cn-iss-install-01 ~]#
[root@cn-iss-install-01 packages]# pvcreate /dev/sdb1
 writing physical volume data to disk "/dev/sdb1"
 physical volume "/dev/sdb1" successfully created
[root@cn-iss-install-01 packages]#
[root@cn-iss-install-01 packages]# vgcreate vg03 /dev/sdb1
 volume group "vg03" successfully created
[root@cn-iss-install-01 packages]# lvcreate -l 83g -n vgdata vg03
[root@cn-iss-install-01 packages]# mke2fs /dev/vg03/vgdata
mke2fs 1.41.12 (17-may-2010)
filesystem label=
os type: linux
block size=4096 (log=2)
fragment size=4096 (log=2)
stride=0 blocks, stripe width=0 blocks
5439488 inodes, 21757952 blocks
1087897 blocks (5.00%) reserved for the super user
first data block=0
maximum filesystem blocks=4294967296
664 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,
        4096000, 7962624, 11239424, 20480000
writing inode tables: done
writing superblocks and filesystem accounting information:
done
this filesystem will be automatically checked every 23 mounts or
180 days, whichever comes first. use tune2fs -c or -i to override.
[root@cn-iss-install-01 packages]#
[root@cn-iss-install-01 packages]#
[root@cn-iss-install-01 packages]# mkf
mkfifo        mkfs.cramfs   mkfs.ext3     mkfs.ext4dev
mkfs          mkfs.ext2     mkfs.ext4
[root@cn-iss-install-01 packages]# mkfs.ext4 /dev/vg03/vgdata
mke2fs 1.41.12 (17-may-2010)
filesystem label=
os type: linux
block size=4096 (log=2)
fragment size=4096 (log=2)
stride=0 blocks, stripe width=0 blocks
5439488 inodes, 21757952 blocks
1087897 blocks (5.00%) reserved for the super user
first data block=0
maximum filesystem blocks=4294967296
664 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,
        4096000, 7962624, 11239424, 20480000
writing inode tables: done
creating journal (32768 blocks): done
writing superblocks and filesystem accounting information: done
this filesystem will be automatically checked every 37 mounts or
180 days, whichever comes first. use tune2fs -c or -i to override.
[root@cn-iss-install-01 packages]#
[root@cn-iss-install-01 spool]# mount /dev/vg03/vgdata /var/spool/repo/
[root@cn-iss-install-01 spool]# cd repo/
[root@cn-iss-install-01 repo]# ls
lost+found
[root@cn-iss-install-01 repo]# pwd
/var/spool/repo
[root@cn-iss-install-01 repo]#
3，常用检查命令：
[root@cn-iss-install-01 /]# pvdisplay
[root@cn-iss-install-01 /]# vgdisplay
[root@cn-iss-install-01 /]# lvdisplay
[root@cn-iss-install-01 /]# pvcreate
 please enter a physical volume path
 run `pvcreate --help' for more information.
[root@cn-iss-install-01 /]# vgcreate
 please provide volume group name and physical volumes
 run `vgcreate --help' for more information.
[root@cn-iss-install-01 /]# lvcreate
 please provide a volume group name
 run `lvcreate --help' for more information.
[root@cn-iss-install-01 /]# vgextend
 please enter volume group name and physical volume(s)
  run `vgextend --help' for more information.
[root@cn-iss-install-01 /]# lvextend
 please specify either size or extents but not both.
 run `lvextend --help' for more information.
[root@cn-iss-install-01 /]#