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LVM应用实例

案例的环境和需求描述如下：公司准备在Internet中搭建邮件服务器（RHEL 6系统平台），面向全国各地的员工及部分VIP客户提供电子邮箱空间。由于用户数量众多，邮件存储需要大量的空间，考虑到动态扩容的需要，计划增加两块SCSI硬盘并构建LVM逻辑卷 (挂载到“/mailbox”目录下）专门用于存放邮件数据。 
根据上述案例环境和需求，推荐的操作步骤如下所述。 

(1 )关闭服务器主机，打开机箱，正确挂接两块SCSI新硬盘。 
(2 )开启服务器主机，并执行“fdisk -I”命令进行检查，确认已识别新增的硬盘（sdb、 sdc )。 
(3)在新磁盘中进行分区，将每块硬盘的所有空间划分为一个独立的主分区，并将分区类型更改为“8e”分好区后使用“fdisk- l”命令查看，确认结果如下所示。

一、格式化、转换分区类型

1.把sdb2转换成LVM类型的分区：

[root@test2 /]# fdisk /dev/sdb

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): t
Partition number (1-4): 2
Hex code (type L to list codes): 8e
Changed system type of partition 2 to 8e (Linux LVM)

Command (m for help): p

Disk /dev/sdb: 85.9 GB, 85899345920 bytes
255 heads, 63 sectors/track, 10443 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: 0xa8f24694

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1        2612    20980858+  83  Linux
/dev/sdb2            2613        5224    20980890   8e  Linux LVM
/dev/sdb3            5225       10443    41921617+  83  Linux

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.
[root@test2 /]#

2.创建sdc2分区，并转变成LVM类型：

[root@test2 /]# fdisk /dev/sdc

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)
2
Invalid partition number for type `2‘
Command action
   e   extended
   p   primary partition (1-4)
p
Partition number (1-4): 2
First cylinder (2613-10443, default 2613):
Using default value 2613
Last cylinder, +cylinders or +size{K,M,G} (2613-10443, default 10443): +20F
Unsupported suffix: ‘F‘.
Supported: 10^N: KB (KiloByte), MB (MegaByte), GB (GigaByte)
            2^N: K  (KibiByte), M  (MebiByte), G  (GibiByte)
Last cylinder, +cylinders or +size{K,M,G} (2613-10443, default 10443): +20G

Command (m for help): P

Disk /dev/sdc: 85.9 GB, 85899345920 bytes
255 heads, 63 sectors/track, 10443 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: 0x8967e34e

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1               1        2612    20980858+  83  Linux
/dev/sdc2            2613        5224    20980890   83  Linux

错误操作：

Command (m for help): T
Partition number (1-4): be
Partition number (1-4): 2
Hex code (type L to list codes): b
Changed system type of partition 2 to b (W95 FAT32)

正确操作：

Command (m for help): t
Partition number (1-4): 2
Hex code (type L to list codes): 8e
Changed system type of partition 2 to 8e (Linux LVM)

Command (m for help): p

Disk /dev/sdc: 85.9 GB, 85899345920 bytes
255 heads, 63 sectors/track, 10443 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: 0x8967e34e

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1               1        2612    20980858+  83  Linux
/dev/sdc2            2613        5224    20980890   8e  Linux LVM

Command (m for help):

3.保存

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)

WARNING: If you have created or modified any DOS 6.x
partitions, please see the fdisk manual page for additional
information.
Syncing disks.

4.探测

探测失败

[root@test2 /]# partx /dev/sdc
sdc   sdc1
[root@test2 /]# partx /dev/sdc
sdc   sdc1
[root@test2 /]# partx -a /dev/sdc
sdc   sdc1
[root@test2 /]# partx -a /dev/sdc
sdc   sdc1

重启：

识别成功：

[root@test2 jason]# partprobe /dev/sdc
sdc   sdc1  sdc2
[root@test2 jason]# partprobe /dev/sdc

当前pv的信息

[root@test2 jason]# pvscan
  PV /dev/sda2   VG vg_jason        lvm2 [19.51 GiB / 0    free]
  PV /dev/sdb1                      lvm2 [20.01 GiB]
  PV /dev/sdb2                      lvm2 [20.01 GiB]
  Total: 3 [59.53 GiB] / in use: 1 [19.51 GiB] / in no VG: 2 [40.02 GiB]
[root@test2 jason]#

二、创建Logical Volume

1.创建pv

将sdc2创建成physical volume(物理卷）：

[root@test2 jason]# pvcreate /dev/sdc2
  Physical volume "/dev/sdc2" successfully created
[root@test2 jason]#

再次查看pv信息：

[root@test2 jason]# pvscan
  PV /dev/sda2   VG vg_jason        lvm2 [19.51 GiB / 0    free]
  PV /dev/sdb1                      lvm2 [20.01 GiB]
  PV /dev/sdb2                      lvm2 [20.01 GiB]
  PV /dev/sdc2                      lvm2 [20.01 GiB]
  Total: 4 [79.53 GiB] / in use: 1 [19.51 GiB] / in no VG: 3 [60.03 GiB]
[root@test2 jason]#

2.创建 VG

vg的信息：

[root@test2 jason]# lvscan
  ACTIVE            ‘/dev/vg_jason/lv_root‘ [17.51 GiB] inherit
  ACTIVE            ‘/dev/vg_jason/lv_swap‘ [2.00 GiB] inherit

创建mail_store的volume group（卷组）：

[root@test2 jason]# pvcreate mail_store /dev/sdb2 /dev/sdc2
  Device mail_store not found (or ignored by filtering).
  dev_is_mpath: failed to get device for 8:18
  Physical volume "/dev/sdb2" successfully created
  Physical volume "/dev/sdc2" successfully created
[root@test2 jason]#

再次查看vg信息：

[root@test2 jason]# vgscan
  Reading all physical volumes.  This may take a while...
  Found volume group "vg_jason" using metadata type lvm2

分析是因为上面的命令用错了，应该是vgcreate，而不是pvcreate

重新创建并查看：

[root@test2 jason]# vgcreate mail_store /dev/sdb2 /dev/sdc2
  Volume group "mail_store" successfully created
[root@test2 jason]# vgscan
  Reading all physical volumes.  This may take a while...
  Found volume group "mail_store" using metadata type lvm2
  Found volume group "vg_jason" using metadata type lvm2
[root@test2 jason]#

mail_store成功创建，并能通过vgscan查找到

[root@test2 jason]# lvcreate -L 35G -n mbox mail_store
  Logical volume "mbox" created
[root@test2 jason]# lvscan
  ACTIVE            ‘/dev/mail_store/mbox‘ [35.00 GiB] inherit
  ACTIVE            ‘/dev/vg_jason/lv_root‘ [17.51 GiB] inherit
  ACTIVE            ‘/dev/vg_jason/lv_swap‘ [2.00 GiB] inherit
[root@test2 jason]#

3.创建LV

创建前的lvscan：

[root@test2 jason]# lvscan
  ACTIVE            ‘/dev/vg_jason/lv_root‘ [17.51 GiB] inherit
  ACTIVE            ‘/dev/vg_jason/lv_swap‘ [2.00 GiB] inherit

创建mbox的lv并查看：

[root@test2 jason]# lvcreate -L 35G -n mbox mail_store
  Logical volume "mbox" created
[root@test2 jason]# lvscan
  ACTIVE            ‘/dev/mail_store/mbox‘ [35.00 GiB] inherit
  ACTIVE            ‘/dev/vg_jason/lv_root‘ [17.51 GiB] inherit
  ACTIVE            ‘/dev/vg_jason/lv_swap‘ [2.00 GiB] inherit
[root@test2 jason]#

创建目录

[root@test2 /]# mkdir /mailbox

4.格式化：

格式化成ext4

[root@test2 /]# mkfs.ext4 /dev/mail_store/mbox
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
2293760 inodes, 9175040 blocks
458752 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
280 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

Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 30 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.
[root@test2 /]#

5.挂载并查看：

[root@test2 /]# mount /dev/mail_store/mbox /mailbox/
[root@test2 /]# df -hT
Filesystem                   Type   Size  Used Avail Use% Mounted on
/dev/mapper/vg_jason-lv_root ext4    18G  4.3G   13G  27% /
tmpfs                        tmpfs  3.9G   72K  3.9G   1% /dev/shm
/dev/sda1                    ext4   485M   40M  421M   9% /boot
/dev/sdc1                    ext4    20G  421M   19G   3% /home
/dev/mapper/mail_store-mbox  ext4    35G  176M   33G   1% /mailbox
[root@test2 /]#

三、拓展篇：

1.在虚拟机中新建一个100G的硬盘（略）：

2.只建一个分区，并转换成为LVM类型：

[root@test2 jason]# fdisk /dev/sdd
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0xef9a8da9.
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 (1-13054, default 1):
Using default value 1
Last cylinder, +cylinders or +size{K,M,G} (1-13054, default 13054):
Using default value 13054

Command (m for help): t
Selected partition 1
Hex code (type L to list codes): 8e
Changed system type of partition 1 to 8e (Linux LVM)

Command (m for help): p

Disk /dev/sdd: 107.4 GB, 107374182400 bytes
255 heads, 63 sectors/track, 13054 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: 0xef9a8da9

   Device Boot      Start         End      Blocks   Id  System
/dev/sdd1               1       13054   104856223+  8e  Linux LVM

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.
[root@test2 jason]#

探测：

[root@test2 jason]# partprobe /dev/sdd
sdd   sdd1
[root@test2 jason]# partprobe /dev/sdd

3.创建pv：

[root@test2 jason]# pvcreate /dev/sdd1
  dev_is_mpath: failed to get device for 8:49
  Physical volume "/dev/sdd1" successfully created

vg拓展mail_store：
[root@test2 jason]# vgextend mail_store /dev/sdd1
  Volume group "mail_store" successfully extended

vgdisplay mail_store：

[root@test2 jason]# vgdisplay mail_store
  --- Volume group ---
  VG Name               mail_store
  System ID
  Format                lvm2
  Metadata Areas        3
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                1
  Open LV               0
  Max PV                0
  Cur PV                3
  Act PV                3
  VG Size               140.01 GiB
  PE Size               4.00 MiB
  Total PE              35843
  Alloc PE / Size       8960 / 35.00 GiB
  Free  PE / Size       26883 / 105.01 GiB
  VG UUID               yHpVfR-lbFL-vs9A-mzgz-m800-JLE2-Dt2z6F

[root@test2 jason]#

4.LV扩容

错误的语法：

[root@test2 jason]# lvextend -L +85G  mbox mail_store
  Path required for Logical Volume "mbox"
  Please provide a volume group name
  Run `lvextend --help‘ for more information.

正确的lv扩容操作：

[root@test2 jason]# lvextend -L +85G /dev/mail_store/mbox
  Extending logical volume mbox to 120.00 GiB
  Logical volume mbox successfully resized

扩容后查看：

[root@test2 jason]# lvscan
  ACTIVE            ‘/dev/mail_store/mbox‘ [120.00 GiB] inherit
  ACTIVE            ‘/dev/vg_jason/lv_root‘ [17.51 GiB] inherit
  ACTIVE            ‘/dev/vg_jason/lv_swap‘ [2.00 GiB] inherit

5.挂载

刚才为了重新加一个100G的硬盘重启，重启后的mount信息：

[root@test2 jason]# df -hT
Filesystem                   Type   Size  Used Avail Use% Mounted on
/dev/mapper/vg_jason-lv_root ext4    18G  4.3G   13G  27% /
tmpfs                        tmpfs  3.9G   72K  3.9G   1% /dev/shm
/dev/sda1                    ext4   485M   40M  421M   9% /boot
/dev/sdc1                    ext4    20G  421M   19G   3% /home
[root@test2 jason]# mount
/dev/mapper/vg_jason-lv_root on / type ext4 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
tmpfs on /dev/shm type tmpfs (rw)
/dev/sda1 on /boot type ext4 (rw)
/dev/sdc1 on /home type ext4 (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
vmware-vmblock on /var/run/vmblock-fuse type fuse.vmware-vmblock (rw,nosuid,nodev,default_permissions,allow_other)

重新挂载并查看：

[root@test2 jason]# mount /dev/mail_store/mbox /mailbox/
[root@test2 jason]# mount
/dev/mapper/vg_jason-lv_root on / type ext4 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
tmpfs on /dev/shm type tmpfs (rw)
/dev/sda1 on /boot type ext4 (rw)
/dev/sdc1 on /home type ext4 (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
vmware-vmblock on /var/run/vmblock-fuse type fuse.vmware-vmblock (rw,nosuid,nodev,default_permissions,allow_other)
/dev/mapper/mail_store-mbox on /mailbox type ext4 (rw)

查看mbox的容量：

[root@test2 jason]# df -hT
Filesystem                   Type   Size  Used Avail Use% Mounted on
/dev/mapper/vg_jason-lv_root ext4    18G  4.3G   13G  27% /
tmpfs                        tmpfs  3.9G   72K  3.9G   1% /dev/shm
/dev/sda1                    ext4   485M   40M  421M   9% /boot
/dev/sdc1                    ext4    20G  421M   19G   3% /home
/dev/mapper/mail_store-mbox  ext4    35G  176M   33G   1% /mailbox

6.更新磁盘容量

查看resize2fs的用法：

[root@test2 jason]# resize2fs
resize2fs 1.41.12 (17-May-2010)
Usage: resize2fs [-d debug_flags] [-f] [-F] [-M] [-P] [-p] device [new_size]

使用resize2fs更新mbox的容量：

[root@test2 jason]# resize2fs /dev/mail_store/mbox
resize2fs 1.41.12 (17-May-2010)
Filesystem at /dev/mail_store/mbox is mounted on /mailbox; on-line resizing required
old desc_blocks = 3, new_desc_blocks = 8
Performing an on-line resize of /dev/mail_store/mbox to 31457280 (4k) blocks.
The filesystem on /dev/mail_store/mbox is now 31457280 blocks long.

更新成功：

[root@test2 jason]# df -hT
Filesystem                   Type   Size  Used Avail Use% Mounted on
/dev/mapper/vg_jason-lv_root ext4    18G  4.3G   13G  27% /
tmpfs                        tmpfs  3.9G   72K  3.9G   1% /dev/shm
/dev/sda1                    ext4   485M   40M  421M   9% /boot
/dev/sdc1                    ext4    20G  421M   19G   3% /home
/dev/mapper/mail_store-mbox  ext4   119G  188M  112G   1% /mailbox
[root@test2 jason]#

本文出自 “11714065” 博客，请务必保留此出处http://11724065.blog.51cto.com/11714065/1790215

LVM应用实例（Dark）

标签：lvm   pv   vg   逻辑卷   物理卷   

原文地址：http://11724065.blog.51cto.com/11714065/1790215