逻辑卷管理案例练习

逻辑卷管理案例练习

需求说明：

因业务的需要，服务器要新增2个10G的磁盘，准备采用逻辑卷对磁盘进行管理。管理员准备如下处理：

1、先对第一块磁盘分区，就分了一个分区，大小为所有容量，现在想就该分区先进行逻辑卷划分，具体规划如下：

（1）对该分区进行逻辑卷管理，卷组名为myvg，逻辑卷名为lv1，大小为5GB。

（2）新建挂载点/mnt/lv1，并格式化逻辑卷lv1，将它挂载至/mnt/lv1来使用。

2、后觉得逻辑卷lv1划分小了，应将它的容量扩至6GB。

3、因第二块磁盘暂时没其他用处，管理员想先将第二块磁盘添加到卷组myvg中，增加卷组的容量。

4、因某种原因，逻辑卷lv1的容量用不上那么大，管理员想将它的容量减至4GB。

5、因第二块磁盘要做他用，所以管理员准备将卷组myvg中的第二块磁盘移除。

步骤：

1、新添加一个磁盘10GB，并将全部大小都划入一个分区

# fdisk /dev/sdb开始划分

Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel Building a new DOS disklabel with disk identifier 0xf8a6f4af.

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): n

Command action

e extended

p primary partition (1-4)

p

Partition number (1-4): 1

First cylinder (1-1305, default 1):

Using default value 1

Last cylinder, +cylinders or +size{K,M,G} (1-1305, default 1305):

Using default value 1305

Command (m for help): p

Disk /dev/sdb: 10.7 GB, 10737418240 bytes

255 heads, 63 sectors/track, 1305 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: 0xf8a6f4af

Device Boot Start End Blocks Id System /dev/sdb1 1 1305 10482381 83 Linux

Command (m for help): w

The partition table has been altered!

Calling ioctl() to re-read partition table.

Syncing disks.

2、创建物理卷

# pvcreate /dev/sdb1

3、查看物理卷

# pvdisplay

"/dev/sdb1" is a new physical volume of "10.00 GiB"

--- NEW Physical volume ---

PV Name /dev/sdb1

VG Name

PV Size 10.00 GiB

Allocatable NO

PE Size 0

Total PE 0

Free PE 0

Allocated PE 0

PV UUID 3czfdh-FlS2-HI9d-ZNEH-fXev-r4Ki-JggFgB 还可以使用命令pvs 和pvscan 查看简略信息。

4、创建卷组，名为myvg

#vgcreate myvg /dev/sdb1

5、查看vg

# vgdisplay

--- Volume group ---

VG Name myvg

System ID

Format lvm2

Metadata Areas 1

Metadata Sequence No 1

VG Access read/write

VG Status resizable

MAX LV 0

Cur LV 0