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 /]#