LVM使用

LVM框架

LVM实验环境准备

创建一个128MB的文件模拟磁盘

[centos@centos lvm]$ dd if=/dev/zero of=./disk.img count=128 bs=1MB
记录了128+0 的读入
记录了128+0 的写出
128000000字节(128 MB)已复制,2.29908 秒,55.7 MB/秒
[centos@centos lvm]$ ls -la --block-size=1MB
总用量 129
drwxrwxr-x.  2 centos centos   1 4月   4 21:41 .
drwx------. 17 centos centos   1 4月   4 21:29 ..
-rw-rw-r--.  1 centos centos 128 4月   4 21:41 disk.img

查看所有的loop设备

[root@centos lvm]# losetup -a
/dev/loop0: [64768]:203857781 (/var/lib/docker/devicemapper/devicemapper/data)
/dev/loop1: [64768]:203857782 (/var/lib/docker/devicemapper/devicemapper/metadata)

查看下一个未使用的loop设备

[root@centos lvm]# losetup -f
/dev/loop2

关联loop设备

[root@centos lvm]# losetup /dev/loop2 disk.img 

使用新磁盘创建新逻辑卷LV

创建LVM分区

[root@centos lvm]# fdisk /dev/loop2
欢迎使用 fdisk (util-linux 2.23.2)。

更改将停留在内存中,直到您决定将更改写入磁盘。
使用写入命令前请三思。

Device does not contain a recognized partition table
使用磁盘标识符 0x823c9167 创建新的 DOS 磁盘标签。

命令(输入 m 获取帮助):n
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p
分区号 (1-4,默认 1):1
起始 扇区 (2048-249999,默认为 2048):
将使用默认值 2048
Last 扇区, +扇区 or +size{K,M,G} (2048-249999,默认为 249999):
将使用默认值 249999
分区 1 已设置为 Linux 类型,大小设为 121.1 MiB

命令(输入 m 获取帮助):t
已选择分区 1
Hex 代码(输入 L 列出所有代码):8e
已将分区“Linux”的类型更改为“Linux LVM”

命令(输入 m 获取帮助):p

磁盘 /dev/loop2:128 MB, 128000000 字节,250000 个扇区
Units = 扇区 of 1 * 512 = 512 bytes
扇区大小(逻辑/物理):512 字节 / 512 字节
I/O 大小(最小/最佳):512 字节 / 512 字节
磁盘标签类型:dos
磁盘标识符:0x823c9167

      设备 Boot      Start         End      Blocks   Id  System
/dev/loop2p1            2048      249999      123976   8e  Linux LVM

命令(输入 m 获取帮助):w
The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 22: 无效的参数.
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)
正在同步磁盘。

重启系统重新关联loop设备

[root@centos centos]# losetup -a
/dev/loop0: [64768]:203857781 (/var/lib/docker/devicemapper/devicemapper/data)
/dev/loop1: [64768]:203857782 (/var/lib/docker/devicemapper/devicemapper/metadata)
[root@centos centos]# losetup -f
/dev/loop2
[root@centos centos]# cd lvm/
[root@centos lvm]# losetup /dev/loop2 disk.img 
[root@centos lvm]# fdisk /dev/loop2
欢迎使用 fdisk (util-linux 2.23.2)。

更改将停留在内存中,直到您决定将更改写入磁盘。
使用写入命令前请三思。


命令(输入 m 获取帮助):p

磁盘 /dev/loop2:128 MB, 128000000 字节,250000 个扇区
Units = 扇区 of 1 * 512 = 512 bytes
扇区大小(逻辑/物理):512 字节 / 512 字节
I/O 大小(最小/最佳):512 字节 / 512 字节
磁盘标签类型:dos
磁盘标识符:0x823c9167

      设备 Boot      Start         End      Blocks   Id  System
/dev/loop2p1            2048      249999      123976   8e  Linux LVM

命令(输入 m 获取帮助):

创建物理卷PV

[root@centos lvm]# pvcreate /dev/loop2
WARNING: dos signature detected on /dev/loop2 at offset 510. Wipe it? [y/n]: y
  Wiping dos signature on /dev/loop2.
  Physical volume "/dev/loop2" successfully created
[root@centos lvm]# pvdisplay 
  --- Physical volume ---
  PV Name               /dev/sda2
  VG Name               centos
  PV Size               49.51 GiB / not usable 3.00 MiB
  Allocatable           yes 
  PE Size               4.00 MiB
  Total PE              12674
  Free PE               11
  Allocated PE          12663
  PV UUID               edqmZj-578L-tMix-DJOE-FFnh-C4n2-aeLIuA
   
  "/dev/loop2" is a new physical volume of "122.07 MiB"
  --- NEW Physical volume ---
  PV Name               /dev/loop2
  VG Name               
  PV Size               122.07 MiB
  Allocatable           NO
  PE Size               0   
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               FyS8OO-sHy3-U297-8FWE-FtS3-TyFh-nzLFZu

创建卷组VG

[root@centos lvm]# vgdisplay 
  --- Volume group ---
  VG Name               centos
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               49.51 GiB
  PE Size               4.00 MiB
  Total PE              12674
  Alloc PE / Size       12663 / 49.46 GiB
  Free  PE / Size       11 / 44.00 MiB
  VG UUID               EQ5hYJ-51Mx-QOd6-yVgZ-BD6A-EhxJ-0QHAqm
   
[root@centos lvm]# vgcreate vgtest /dev/loop2
  Volume group "vgtest" successfully created
[root@centos lvm]# vgdisplay 
  --- Volume group ---
  VG Name               centos
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               49.51 GiB
  PE Size               4.00 MiB
  Total PE              12674
  Alloc PE / Size       12663 / 49.46 GiB
  Free  PE / Size       11 / 44.00 MiB
  VG UUID               EQ5hYJ-51Mx-QOd6-yVgZ-BD6A-EhxJ-0QHAqm
   
  --- Volume group ---
  VG Name               vgtest
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  1
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                0
  Open LV               0
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               120.00 MiB
  PE Size               4.00 MiB
  Total PE              30
  Alloc PE / Size       0 / 0   
  Free  PE / Size       30 / 120.00 MiB
  VG UUID               g0JNXo-zxhI-4QQ3-eGsi-3xnm-aNXe-Vscq4A

[root@centos lvm]# lvcreate -L 120M -n vps /dev/vgtest
  Logical volume "vps" created.
[root@centos lvm]# lvdisplay
  --- Logical volume ---
  LV Path                /dev/centos/swap
  LV Name                swap
  VG Name                centos
  LV UUID                EwWI53-xxB2-dXlQ-xuIb-8xRa-BDpE-THn1bE
  LV Write Access        read/write
  LV Creation host, time centos, 2016-03-30 17:44:27 +0800
  LV Status              available
  # open                 2
  LV Size                2.00 GiB
  Current LE             512
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:1
   
  --- Logical volume ---
  LV Path                /dev/centos/root
  LV Name                root
  VG Name                centos
  LV UUID                smMyzH-3MQ4-uTib-8b9I-FVd5-qBvv-6Y5I7N
  LV Write Access        read/write
  LV Creation host, time centos, 2016-03-30 17:44:27 +0800
  LV Status              available
  # open                 1
  LV Size                47.46 GiB
  Current LE             12151
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:0
   
  --- Logical volume ---
  LV Path                /dev/vgtest/vps
  LV Name                vps
  VG Name                vgtest
  LV UUID                EzFbN3-TKqF-bBuC-buCu-dlib-vPwi-6atqtr
  LV Write Access        read/write
  LV Creation host, time centos, 2016-04-04 22:19:50 +0800
  LV Status              available
  # open                 0
  LV Size                120.00 MiB
  Current LE             30
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:3

格式化LV逻辑卷为ext4文件系统格式

[root@centos lvm]# mkfs.ext4 /dev/vgtest/vps 
mke2fs 1.42.9 (28-Dec-2013)
Discarding device blocks: 完成                            
文件系统标签=
OS type: Linux
块大小=1024 (log=0)
分块大小=1024 (log=0)
Stride=0 blocks, Stripe width=0 blocks
30720 inodes, 122880 blocks
6144 blocks (5.00%) reserved for the super user
第一个数据块=1
Maximum filesystem blocks=33685504
15 block groups
8192 blocks per group, 8192 fragments per group
2048 inodes per group
Superblock backups stored on blocks: 
    8193, 24577, 40961, 57345, 73729

Allocating group tables: 完成                            
正在写入inode表: 完成                            
Creating journal (4096 blocks): 完成
Writing superblocks and filesystem accounting information: 完成 

挂载LVM目录到文件系统

[centos@centos ~]$ mkdir vps
[centos@centos ~]$ sudo mount -t ext4 /dev/vgtest/vps vps/
[centos@centos ~]$ df -h
文件系统                 容量  已用  可用 已用% 挂载点
/dev/mapper/centos-root   48G  4.4G   44G   10% /
devtmpfs                 978M     0  978M    0% /dev
tmpfs                    993M  152K  993M    1% /dev/shm
tmpfs                    993M  9.0M  984M    1% /run
tmpfs                    993M     0  993M    0% /sys/fs/cgroup
/dev/sda1                497M  140M  357M   29% /boot
tmpfs                    199M  4.0K  199M    1% /run/user/42
tmpfs                    199M   12K  199M    1% /run/user/1000
/dev/mapper/vgtest-vps   113M  1.6M  103M    2% /home/centos/vps

由于这边关联的/dev/loop2设备每次系统重启后就自动detach,原因未知,所以这边没配置开机自动挂载了

删除逻辑卷LV

umount逻辑卷

[root@centos centos]# df -h
文件系统                 容量  已用  可用 已用% 挂载点
/dev/mapper/centos-root   48G  4.4G   44G   10% /
devtmpfs                 978M     0  978M    0% /dev
tmpfs                    993M  156K  993M    1% /dev/shm
tmpfs                    993M  9.0M  985M    1% /run
tmpfs                    993M     0  993M    0% /sys/fs/cgroup
/dev/sda1                497M  140M  357M   29% /boot
tmpfs                    199M   16K  199M    1% /run/user/1000
/dev/mapper/vgtest-vps   113M  1.6M  103M    2% /home/centos/vps
[root@centos centos]# umount /home/centos/vps

删除逻辑卷LV

[root@centos centos]# lvremove /dev/vgtest/vps 
Do you really want to remove active logical volume vps? [y/n]: y
  Logical volume "vps" successfully removed
[root@centos centos]# lvdisplay 
  --- Logical volume ---
  LV Path                /dev/centos/swap
  LV Name                swap
  VG Name                centos
  LV UUID                EwWI53-xxB2-dXlQ-xuIb-8xRa-BDpE-THn1bE
  LV Write Access        read/write
  LV Creation host, time centos, 2016-03-30 17:44:27 +0800
  LV Status              available
  # open                 2
  LV Size                2.00 GiB
  Current LE             512
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:1
   
  --- Logical volume ---
  LV Path                /dev/centos/root
  LV Name                root
  VG Name                centos
  LV UUID                smMyzH-3MQ4-uTib-8b9I-FVd5-qBvv-6Y5I7N
  LV Write Access        read/write
  LV Creation host, time centos, 2016-03-30 17:44:27 +0800
  LV Status              available
  # open                 1
  LV Size                47.46 GiB
  Current LE             12151
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:0

删除卷组VG

[root@centos centos]# vgremove vgtest 
  Volume group "vgtest" successfully removed
[root@centos centos]# vgdisplay 
  --- Volume group ---
  VG Name               centos
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               49.51 GiB
  PE Size               4.00 MiB
  Total PE              12674
  Alloc PE / Size       12663 / 49.46 GiB
  Free  PE / Size       11 / 44.00 MiB
  VG UUID               EQ5hYJ-51Mx-QOd6-yVgZ-BD6A-EhxJ-0QHAqm

删除物理卷PV

[root@centos centos]# pvremove /dev/loop2
  Labels on physical volume "/dev/loop2" successfully wiped
[root@centos centos]# pvdisplay 
  --- Physical volume ---
  PV Name               /dev/sda2
  VG Name               centos
  PV Size               49.51 GiB / not usable 3.00 MiB
  Allocatable           yes 
  PE Size               4.00 MiB
  Total PE              12674
  Free PE               11
  Allocated PE          12663
  PV UUID               edqmZj-578L-tMix-DJOE-FFnh-C4n2-aeLIuA

扩大逻辑卷LV大小

恢复删除逻辑卷LV之前的状态,再创建一个新的磁盘文件作为扩展文件

[root@centos lvm]# dd if=/dev/zero of=./disk_ext.img count=128 bs=1MB
记录了128+0 的读入
记录了128+0 的写出
128000000字节(128 MB)已复制,0.39764 秒,322 MB/秒
[root@centos lvm]# losetup -f
/dev/loop3
[root@centos lvm]# losetup /dev/loop3 disk_ext.img 
[root@centos lvm]# fdisk /dev/loop3
欢迎使用 fdisk (util-linux 2.23.2)。

更改将停留在内存中,直到您决定将更改写入磁盘。
使用写入命令前请三思。

Device does not contain a recognized partition table
使用磁盘标识符 0x0ca75082 创建新的 DOS 磁盘标签。

命令(输入 m 获取帮助):n
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p
分区号 (1-4,默认 1):1
起始 扇区 (2048-249999,默认为 2048):
将使用默认值 2048
Last 扇区, +扇区 or +size{K,M,G} (2048-249999,默认为 249999):
将使用默认值 249999
分区 1 已设置为 Linux 类型,大小设为 121.1 MiB

命令(输入 m 获取帮助):t
已选择分区 1
Hex 代码(输入 L 列出所有代码):8e
已将分区“Linux”的类型更改为“Linux LVM”

命令(输入 m 获取帮助):p

磁盘 /dev/loop3:128 MB, 128000000 字节,250000 个扇区
Units = 扇区 of 1 * 512 = 512 bytes
扇区大小(逻辑/物理):512 字节 / 512 字节
I/O 大小(最小/最佳):512 字节 / 512 字节
磁盘标签类型:dos
磁盘标识符:0x0ca75082

      设备 Boot      Start         End      Blocks   Id  System
/dev/loop3p1            2048      249999      123976   8e  Linux LVM

命令(输入 m 获取帮助):w
The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 22: 无效的参数.
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)
正在同步磁盘。
[root@centos lvm]# partprobe

创建新的物理卷PV

[root@centos lvm]# pvcreate /dev/loop3
WARNING: dos signature detected on /dev/loop3 at offset 510. Wipe it? [y/n]: y
  Wiping dos signature on /dev/loop3.
  Physical volume "/dev/loop3" successfully created
[root@centos lvm]# pvdisplay 
  --- Physical volume ---
  PV Name               /dev/loop2
  VG Name               vgtest
  PV Size               122.07 MiB / not usable 2.07 MiB
  Allocatable           yes (but full)
  PE Size               4.00 MiB
  Total PE              30
  Free PE               0
  Allocated PE          30
  PV UUID               TuUTR0-FeaK-FL23-QIIh-qPeC-cXmf-FF32by
   
  --- Physical volume ---
  PV Name               /dev/sda2
  VG Name               centos
  PV Size               49.51 GiB / not usable 3.00 MiB
  Allocatable           yes 
  PE Size               4.00 MiB
  Total PE              12674
  Free PE               11
  Allocated PE          12663
  PV UUID               edqmZj-578L-tMix-DJOE-FFnh-C4n2-aeLIuA
   
  "/dev/loop3" is a new physical volume of "122.07 MiB"
  --- NEW Physical volume ---
  PV Name               /dev/loop3
  VG Name               
  PV Size               122.07 MiB
  Allocatable           NO
  PE Size               0   
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               LLFy8f-YNua-YSp1-QByK-RqMv-PTii-t9DY9U

扩展卷组VG的大小

[root@centos lvm]# vgdisplay vgtest 
  --- Volume group ---
  VG Name               vgtest
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  2
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                1
  Open LV               1
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               120.00 MiB
  PE Size               4.00 MiB
  Total PE              30
  Alloc PE / Size       30 / 120.00 MiB
  Free  PE / Size       0 / 0   
  VG UUID               tfTiUi-mNAe-1JTs-cOfy-AnKj-FKM1-wSSfJs

[root@centos lvm]# vgextend vgtest /dev/loop3
  Volume group "vgtest" successfully extended
[root@centos lvm]# vgdisplay vgtest 
  --- Volume group ---
  VG Name               vgtest
  System ID             
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                1
  Open LV               1
  Max PV                0
  Cur PV                2
  Act PV                2
  VG Size               240.00 MiB
  PE Size               4.00 MiB
  Total PE              60
  Alloc PE / Size       30 / 120.00 MiB
  Free  PE / Size       30 / 120.00 MiB
  VG UUID               tfTiUi-mNAe-1JTs-cOfy-AnKj-FKM1-wSSfJs

扩展逻辑卷LV大小

[root@centos lvm]# lvextend -L +20M /dev/vgtest/vps 
  Size of logical volume vgtest/vps changed from 120.00 MiB (30 extents) to 140.00 MiB (35 extents).
  Logical volume vps successfully resized.
[root@centos lvm]# lvdisplay /dev/vgtest/vps | grep "LV Size"
  LV Size                140.00 MiB
[root@centos lvm]# vgdisplay vgtest | grep "Free  PE / Size"
  Free  PE / Size       25 / 100.00 MiB 

扩展文件系统大小

[root@centos lvm]# e2fsck -f /dev/vgtest/vps 
e2fsck 1.42.9 (28-Dec-2013)
第一步: 检查inode,块,和大小
第二步: 检查目录结构
第3步: 检查目录连接性
Pass 4: Checking reference counts
第5步: 检查簇概要信息
/dev/vgtest/vps: 11/30720 files (9.1% non-contiguous), 9529/122880 blocks
[root@centos lvm]# resize2fs /dev/vgtest/vps 
resize2fs 1.42.9 (28-Dec-2013)
Resizing the filesystem on /dev/vgtest/vps to 143360 (1k) blocks.
The filesystem on /dev/vgtest/vps is now 143360 blocks long.

[root@centos lvm]# mount /dev/vgtest/vps ../vps/

缩小逻辑卷LV大小

umount逻辑卷

[root@centos lvm]# df -h
文件系统                 容量  已用  可用 已用% 挂载点
/dev/mapper/centos-root   48G  4.5G   43G   10% /
devtmpfs                 978M     0  978M    0% /dev
tmpfs                    993M  156K  993M    1% /dev/shm
tmpfs                    993M  9.0M  985M    1% /run
tmpfs                    993M     0  993M    0% /sys/fs/cgroup
/dev/sda1                497M  140M  357M   29% /boot
tmpfs                    199M   16K  199M    1% /run/user/1000
/dev/mapper/vgtest-vps   132M  1.6M  121M    2% /home/centos/vps
[root@centos lvm]# umount /home/centos/vps
[root@centos lvm]# lvdisplay /dev/vgtest/vps | grep "LV Size"
  LV Size                140.00 MiB

检查文件系统整合性,然后缩小文件系统大小

[root@centos lvm]# e2fsck -f /dev/vgtest/vps
e2fsck 1.42.9 (28-Dec-2013)
第一步: 检查inode,块,和大小
第二步: 检查目录结构
第3步: 检查目录连接性
Pass 4: Checking reference counts
第5步: 检查簇概要信息
/dev/vgtest/vps: 11/36864 files (9.1% non-contiguous), 10303/143360 blocks
[root@centos lvm]# resize2fs /dev/vgtest/vps 100M
resize2fs 1.42.9 (28-Dec-2013)
Resizing the filesystem on /dev/vgtest/vps to 102400 (1k) blocks.
The filesystem on /dev/vgtest/vps is now 102400 blocks long.

缩小逻辑卷LV大小,大小和文件系统保持一致

[root@centos lvm]# lvreduce -L 100M /dev/vgtest/vps 
  WARNING: Reducing active logical volume to 100.00 MiB
  THIS MAY DESTROY YOUR DATA (filesystem etc.)
Do you really want to reduce vps? [y/n]: y
  Size of logical volume vgtest/vps changed from 140.00 MiB (35 extents) to 100.00 MiB (25 extents).
  Logical volume vps successfully resized.
[root@centos lvm]# lvdisplay /dev/vgtest/vps | grep "LV Size"
  LV Size                100.00 MiB
[root@centos lvm]# vgdisplay vgtest | grep "Free  PE / Size"
  Free  PE / Size       35 / 140.00 MiB

扩展VMWare虚拟机的磁盘大小

给VMWare虚拟机新增一块硬盘

查询当前磁盘使用情况

[root@centos centos]# fdisk -l

磁盘 /dev/sda:53.7 GB, 53687091200 字节,104857600 个扇区
Units = 扇区 of 1 * 512 = 512 bytes
扇区大小(逻辑/物理):512 字节 / 512 字节
I/O 大小(最小/最佳):512 字节 / 512 字节
磁盘标签类型:dos
磁盘标识符:0x000bc6c9

   设备 Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048     1026047      512000   83  Linux
/dev/sda2         1026048   104857599    51915776   8e  Linux LVM

磁盘 /dev/sdb:21.5 GB, 21474836480 字节,41943040 个扇区
Units = 扇区 of 1 * 512 = 512 bytes
扇区大小(逻辑/物理):512 字节 / 512 字节
I/O 大小(最小/最佳):512 字节 / 512 字节


磁盘 /dev/mapper/centos-root:51.0 GB, 50964987904 字节,99540992 个扇区
Units = 扇区 of 1 * 512 = 512 bytes
扇区大小(逻辑/物理):512 字节 / 512 字节
I/O 大小(最小/最佳):512 字节 / 512 字节


磁盘 /dev/mapper/centos-swap:2147 MB, 2147483648 字节,4194304 个扇区
Units = 扇区 of 1 * 512 = 512 bytes
扇区大小(逻辑/物理):512 字节 / 512 字节
I/O 大小(最小/最佳):512 字节 / 512 字节

[root@centos centos]# 

在新增的磁盘上创建LVM分区

[root@centos centos]# fdisk /dev/sdb 
欢迎使用 fdisk (util-linux 2.23.2)。

更改将停留在内存中,直到您决定将更改写入磁盘。
使用写入命令前请三思。

Device does not contain a recognized partition table
使用磁盘标识符 0x76206a7b 创建新的 DOS 磁盘标签。

命令(输入 m 获取帮助):n
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p
分区号 (1-4,默认 1):1
起始 扇区 (2048-41943039,默认为 2048):
将使用默认值 2048
Last 扇区, +扇区 or +size{K,M,G} (2048-41943039,默认为 41943039):
将使用默认值 41943039
分区 1 已设置为 Linux 类型,大小设为 20 GiB

命令(输入 m 获取帮助):t
已选择分区 1
Hex 代码(输入 L 列出所有代码):8e
已将分区“Linux”的类型更改为“Linux LVM”

命令(输入 m 获取帮助):p

磁盘 /dev/sdb:21.5 GB, 21474836480 字节,41943040 个扇区
Units = 扇区 of 1 * 512 = 512 bytes
扇区大小(逻辑/物理):512 字节 / 512 字节
I/O 大小(最小/最佳):512 字节 / 512 字节
磁盘标签类型:dos
磁盘标识符:0x76206a7b

   设备 Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048    41943039    20970496   8e  Linux LVM

命令(输入 m 获取帮助):w
The partition table has been altered!

Calling ioctl() to re-read partition table.
正在同步磁盘。
[root@centos centos]# partprobe

创建物理卷PV

[root@centos centos]# fdisk -l /dev/sdb 

磁盘 /dev/sdb:21.5 GB, 21474836480 字节,41943040 个扇区
Units = 扇区 of 1 * 512 = 512 bytes
扇区大小(逻辑/物理):512 字节 / 512 字节
I/O 大小(最小/最佳):512 字节 / 512 字节
磁盘标签类型:dos
磁盘标识符:0x76206a7b

   设备 Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048    41943039    20970496   8e  Linux LVM
[root@centos centos]# pvcreate /dev/sdb1
  Physical volume "/dev/sdb1" successfully created

扩展卷组大小

[root@centos centos]# pvdisplay 
  --- Physical volume ---
  PV Name               /dev/sda2
  VG Name               centos
  PV Size               49.51 GiB / not usable 3.00 MiB
  Allocatable           yes 
  PE Size               4.00 MiB
  Total PE              12674
  Free PE               11
  Allocated PE          12663
  PV UUID               edqmZj-578L-tMix-DJOE-FFnh-C4n2-aeLIuA
   
  "/dev/sdb1" is a new physical volume of "20.00 GiB"
  --- NEW Physical volume ---
  PV Name               /dev/sdb1
  VG Name               
  PV Size               20.00 GiB
  Allocatable           NO
  PE Size               0   
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               OqMQ6E-KYgh-W4Kl-OvEW-dUIZ-i1BJ-hZz9cg
   
[root@centos centos]# vgdisplay 
  --- Volume group ---
  VG Name               centos
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               49.51 GiB
  PE Size               4.00 MiB
  Total PE              12674
  Alloc PE / Size       12663 / 49.46 GiB
  Free  PE / Size       11 / 44.00 MiB
  VG UUID               EQ5hYJ-51Mx-QOd6-yVgZ-BD6A-EhxJ-0QHAqm
   
[root@centos centos]# vgextend centos /dev/sdb1
  Volume group "centos" successfully extended
[root@centos centos]# vgdisplay centos |grep 'Free  PE / Size'
  Free  PE / Size       5130 / 20.04 GiB

扩展逻辑卷LV大小

[root@centos centos]# lvdisplay 
  --- Logical volume ---
  LV Path                /dev/centos/swap
  LV Name                swap
  VG Name                centos
  LV UUID                EwWI53-xxB2-dXlQ-xuIb-8xRa-BDpE-THn1bE
  LV Write Access        read/write
  LV Creation host, time centos, 2016-03-30 17:44:27 +0800
  LV Status              available
  # open                 2
  LV Size                2.00 GiB
  Current LE             512
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:1
   
  --- Logical volume ---
  LV Path                /dev/centos/root
  LV Name                root
  VG Name                centos
  LV UUID                smMyzH-3MQ4-uTib-8b9I-FVd5-qBvv-6Y5I7N
  LV Write Access        read/write
  LV Creation host, time centos, 2016-03-30 17:44:27 +0800
  LV Status              available
  # open                 1
  LV Size                47.46 GiB
  Current LE             12151
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:0
   
[root@centos centos]# lvextend -L +20G /dev/centos/root
  Size of logical volume centos/root changed from 47.46 GiB (12151 extents) to 67.46 GiB (17271 extents).
  Logical volume root successfully resized.

扩展文件系统大小

[root@centos centos]# xfs_growfs /dev/centos/root 
meta-data=/dev/mapper/centos-root isize=256    agcount=4, agsize=3110656 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=0        finobt=0
data     =                       bsize=4096   blocks=12442624, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=0
log      =internal               bsize=4096   blocks=6075, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 12442624 to 17685504
[root@centos centos]# df -h
文件系统                 容量  已用  可用 已用% 挂载点
/dev/mapper/centos-root   68G  3.4G   65G    5% /
devtmpfs                 978M     0  978M    0% /dev
tmpfs                    993M  156K  993M    1% /dev/shm
tmpfs                    993M  9.0M  984M    1% /run
tmpfs                    993M     0  993M    0% /sys/fs/cgroup
/dev/sda1                497M  140M  357M   29% /boot
tmpfs                    199M  4.0K  199M    1% /run/user/42
tmpfs                    199M  8.0K  199M    1% /run/user/1000
[root@centos centos]# 

问题处理

centos7下使用resize2fs报错,产生原因是因为centos7下有些分区使用的是xfs的文件系统,需要使用 xfs_growfs 命令替代

[root@centos centos]# resize2fs -p /dev/centos/root
resize2fs 1.42.9 (28-Dec-2013)
resize2fs: Bad magic number in super-block 当尝试打开 /dev/centos/root 时
找不到有效的文件系统超级块.
[root@centos centos]# df -T
文件系统                类型        1K-块    已用     可用 已用% 挂载点
/dev/mapper/centos-root xfs      49746196 3526408 46219788    8% /
devtmpfs                devtmpfs  1001232       0  1001232    0% /dev
tmpfs                   tmpfs     1016776     156  1016620    1% /dev/shm
tmpfs                   tmpfs     1016776    9160  1007616    1% /run
tmpfs                   tmpfs     1016776       0  1016776    0% /sys/fs/cgroup
/dev/sda1               xfs        508588  143176   365412   29% /boot
tmpfs                   tmpfs      203356       4   203352    1% /run/user/42
tmpfs                   tmpfs      203356       8   203348    1% /run/user/1000

参考

http://www.litvip.com/category/lvm%E4%BD%BF%E7%94%A8/

原文地址:https://www.cnblogs.com/silvermagic/p/7665800.html