Linux LVM

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作者: huasheng(http://huasheng.itpub.net)
发表于: 2004.11.22 17:10
分类: 操作系统
出处: http://huasheng.itpub.net/post/1210/6334
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Linux LVM

 

 

 

 

目的：将2块20G的硬盘做成一个35G的卷。

 

 

步骤：

 

 

1. 在硬盘上创建一个LVM分区。使用fdisk或者其它的分区工具来创建一个LVM分区。Linux LVM的分区类型为8e。

# fdisk /dev/hdb

 

# fdisk /dev/hdd

 

 

 

1. 初始化磁盘或磁盘分区：

# pvcreate /dev/hdb1

 

pvcreate -- physical volume "/dev/hdb1" successfully created

 

 

 

# pvcreate /dev/hdd1

 

pvcreate -- physical volume "/dev/hdd1" successfully created

 

 

 

1. 创建卷组：

#vgcreate main_vlm /dev/hdb1 /dev/hdd1

 

vgcreate -- INFO: using default physical extent size 4 MB

 

vgcreate -- INFO: maximum logical volume size is 255.99 Gigabyte

 

vgcreate -- doing automatic backup of volume group "main_vlm"

 

vgcreate -- volume group "main_vlm" successfully created and activated

 

 

 

1. 激活卷组：

    

#vgchange -a y main_vlm

 

vgchange -- volume group "main_vlm" already active

 

 

 

1. 删除卷组：

    

#vgchange -a n main_vlm       去激活

 

#vgremove main_vlm            删除

 

 

 

1. 添加一个物理卷至卷组

    

 

 

#vgextend main_vlm /dev/hdb2

 

 

 

1. 从卷组中移去一个物理卷

    

#vgreduce main_vlm /dev/hdb2

 

 

 

1. 查看所建立卷组的细节信息：

    

#vgdisplay

--- Volume group ---

VG Name               main_vlm

VG Access             read/write

VG Status             available/resizable

VG #                  0

MAX LV                256

Cur LV                0

Open LV               0

MAX LV Size           255.99 GB

Max PV                256

Cur PV                2

Act PV                2

VG Size               37.23 GB

PE Size               4 MB

Total PE              9532

Alloc PE / Size       0 / 0

Free  PE / Size       9532 / 37.23 GB

VG UUID               GX1KHB-YqZM-3DKe-2z9q-h4Kh-eS3g-2rcq9u

 

 

1. 创建一个逻辑卷：

# lvcreate -L35G -nlogvol1 main_vlm

 

lvcreate -- doing automatic backup of "main_vlm"

 

lvcreate -- logical volume "/dev/main_vlm/logvol1" successfully created

 

 

1. 移去一个逻辑卷：

#lvremove /dev/main_vlm/logvol1

 

 

1. 减小逻辑卷大小的方法：

# lvreduce -L-5G /dev/main_vlm/logvol1

 

lvreduce -- WARNING: reducing active and open logical volume to 29.99 GB

 

lvreduce -- THIS MAY DESTROY YOUR DATA (filesystem etc.)

 

lvreduce -- do you really want to reduce "/dev/main_vlm/logvol1"? [y/n]: y

 

lvreduce -- doing automatic backup of volume group "main_vlm"

 

lvreduce -- logical volume "/dev/main_vlm/logvol1" successfully reduced

 

 

1. 增加逻辑卷大小的方法：

#lvextend -L+5G /dev/main_vlm/logvol1

 

lvextend -- extending logical volume "/dev/main_vlm/logvol1" to 34.99 GB

 

lvextend -- doing automatic backup of volume group "main_vlm"

 

lvextend -- logical volume "/dev/main_vlm/logvol1" successfully extended

 

 

1. 创建文件系统：

[root@labgw /]# mke2fs /dev/main_vlm/logvol1

 

mke2fs 1.32 (09-Nov-2002)

 

Filesystem label=

 

OS type: Linux

 

Block size=4096 (log=2)

 

Fragment size=4096 (log=2)

 

4587520 inodes, 9175040 blocks

 

458752 blocks (5.00%) reserved for the super user

 

First data block=0

 

280 block groups

 

32768 blocks per group, 32768 fragments per group

 

16384 inodes per group

 

Superblock backups stored on blocks:

 

        32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,

 

        4096000, 7962624

 

 

 

Writing inode tables: done                           

 

Writing superblocks and filesystem accounting information:

 

 

1. 使用mount命令来加载新创建的文件系统：

#mount /dev/main_vlm/logvol1 /mnt/movie/

 

 

1. 在/etc/fstab中加入以下入口，在启动时加载文件系统：

#vi /etc/fstab

/dev/main_lvm/logvol1   /mnt/movie              ext3    defaults        1 1