LVM逻辑卷

文章目录

• • 磁盘分区（可选）
  • 刷新分区表
  • 创建PV物理卷
  • 创建VG逻辑卷组
  • 创建LV逻辑卷
  • • 挂载磁盘
  • 扩容LV逻辑卷

[root@localhost ~]# lsblk
NAME            MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda               8:0    0  100G  0 disk
├─sda1            8:1    0    1G  0 part /boot
└─sda2            8:2    0   99G  0 part
  ├─centos-root 253:0    0   95G  0 lvm  /
  └─centos-swap 253:1    0    4G  0 lvm  [SWAP]
sdb               8:16   0   20G  0 disk        # 增加的磁盘已经读取到了
sr0              11:0    1 1024M  0 rom

磁盘分区（可选）

[root@localhost ~]# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.2).

Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0x5d15236d.

Command (m for help): p     # 查看磁盘信息

Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x5d15236d

   Device Boot      Start         End      Blocks   Id  System

Command (m for help): n    # 新建分区
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p   # p为主分区，e为扩展分区（最多四个主分区，如果需要更多分区，第四个分区可以选为扩展分区）
Partition number (1-4, default 1): 1     # 选择分区，1为第一个主分区
First sector (2048-41943039, default 2048):   # 起始扇区，安装默认的即可
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-41943039, default 41943039): +10G   # 分10G
Partition 1 of type Linux and of size 10 GiB is set

Command (m for help): n    # 继续新建分区
Partition type:
   p   primary (1 primary, 0 extended, 3 free)   # 已经现实有一个主分区了
   e   extended
Select (default p): p    # 再次新建一个主分区
Partition number (2-4, default 2):    # 默认主分区
First sector (20973568-41943039, default 20973568):    # 默认起始扇区
Using default value 20973568
Last sector, +sectors or +size{K,M,G} (20973568-41943039, default 41943039):   # 全部使用
Using default value 41943039
Partition 2 of type Linux and of size 10 GiB is set

Command (m for help): w    # 按w则退出分区模式，写入磁盘，但未生效
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

刷新分区表

[root@localhost ~]# partprobe /dev/sdb    # 刷新分区表
[root@localhost ~]# lsblk    # sdb已经分为两个区了，各10G
NAME            MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda               8:0    0  100G  0 disk
├─sda1            8:1    0    1G  0 part /boot
└─sda2            8:2    0   99G  0 part
  ├─centos-root 253:0    0   95G  0 lvm  /
  └─centos-swap 253:1    0    4G  0 lvm  [SWAP]
sdb               8:16   0   20G  0 disk
├─sdb1            8:17   0   10G  0 part
└─sdb2            8:18   0   10G  0 part
sr0              11:0    1 1024M  0 rom

创建PV物理卷

[root@localhost ~]# pvcreate /dev/sdb{1,2}   # 将sdb1和sdb2两个分区创建成pv物理卷
  Physical volume "/dev/sdb1" successfully created.
  Physical volume "/dev/sdb2" successfully created.

• 查看pv物理卷

[root@localhost ~]# pvs
  PV         VG     Fmt  Attr PSize   PFree
  /dev/sda2  centos lvm2 a--  <99.00g      0
  /dev/sdb1         lvm2 ---   10.00g  10.00g
  /dev/sdb2         lvm2 ---  <10.00g <10.00g

创建VG逻辑卷组

[root@localhost ~]# vgcreate vg-sdb /dev/sdb{1,2}   # 将sdb1和sdb2两个分区创建成VG卷组，名字为vg-sdb
  Volume group "vg-sdb" successfully created

• 查看vg卷组

[root@localhost ~]# 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               <99.00 GiB
  PE Size               4.00 MiB
  Total PE              25343
  Alloc PE / Size       25343 / <99.00 GiB
  Free  PE / Size       0 / 0
  VG UUID               Z1h9Gu-7UmL-80jT-MqyZ-rU8p-ys6a-Eg6Mcu

  --- Volume group ---
  VG Name               vg-sdb
  System ID
  Format                lvm2
  Metadata Areas        2
  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                2
  Act PV                2
  VG Size               19.99 GiB   # VG卷组20G
  PE Size               4.00 MiB
  Total PE              5118
  Alloc PE / Size       0 / 0
  Free  PE / Size       5118 / 19.99 GiB
  VG UUID               FIk0Yn-leBU-XUWE-nqtv-Odi2-oSFC-Qscyu7

创建LV逻辑卷

[root@localhost ~]# lvcreate -L 10G -n lv-sdb vg-sdb   # 创建一个10G，名为lv-sdb，从vg-sdb卷组获取空间
  Logical volume "lv-sdb" created.
[root@localhost ~]# lvs   # 查看lv逻辑卷
  LV     VG     Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root   centos -wi-ao---- <95.00g
  swap   centos -wi-ao----   4.00g
  lv-sdb vg-sdb -wi-a-----  10.00g
[root@localhost ~]# mkfs.ext4 /dev/vg-sdb/lv-sdb   # 创建文件系统（xfs使用mkfs.xfs）
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
655360 inodes, 2621440 blocks
131072 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2151677952
80 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

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

挂载磁盘

[root@localhost ~]# mkdir /mnt/lv-sdb
[root@localhost ~]# mount /dev/vg-sdb/lv-sdb /mnt/lv-sdb
[root@localhost ~]# df -Th
Filesystem                  Type      Size  Used Avail Use% Mounted on
/dev/mapper/centos-root     xfs        95G   16G   80G  17% /
devtmpfs                    devtmpfs  979M     0  979M   0% /dev
tmpfs                       tmpfs     991M     0  991M   0% /dev/shm
tmpfs                       tmpfs     991M  9.6M  981M   1% /run
tmpfs                       tmpfs     991M     0  991M   0% /sys/fs/cgroup
/dev/sda1                   xfs      1014M  133M  882M  14% /boot
tmpfs                       tmpfs     199M     0  199M   0% /run/user/0
/dev/mapper/vg--sdb-lv--sdb ext4      9.8G   37M  9.2G   1% /mnt/lv-sdb

扩容LV逻辑卷

[root@localhost ~]# 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               <99.00 GiB
  PE Size               4.00 MiB
  Total PE              25343
  Alloc PE / Size       25343 / <99.00 GiB
  Free  PE / Size       0 / 0
  VG UUID               Z1h9Gu-7UmL-80jT-MqyZ-rU8p-ys6a-Eg6Mcu

  --- Volume group ---
  VG Name               vg-sdb
  System ID
  Format                lvm2
  Metadata Areas        2
  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                2
  Act PV                2
  VG Size               19.99 GiB
  PE Size               4.00 MiB
  Total PE              5118
  Alloc PE / Size       2560 / 10.00 GiB
  Free  PE / Size       2558 / 9.99 GiB     # vg卷组还有10G的空间
  VG UUID               FIk0Yn-leBU-XUWE-nqtv-Odi2-oSFC-Qscyu7
[root@localhost ~]# lvextend -L +9.9G /dev/vg-sdb/lv-sdb   # 扩展9.9G给lv-sdb逻辑卷
  Rounding size to boundary between physical extents: 9.90 GiB.
  Size of logical volume vg-sdb/lv-sdb changed from 10.00 GiB (2560 extents) to 19.90 GiB (5095 extents).
  Logical volume vg-sdb/lv-sdb successfully resized.
[root@localhost ~]# lvs   # 查看lv逻辑卷容量
  LV     VG     Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root   centos -wi-ao---- <95.00g
  swap   centos -wi-ao----   4.00g
  lv-sdb vg-sdb -wi-ao----  19.90g
[root@localhost ~]# resize2fs /dev/vg-sdb/lv-sdb    # 刷新磁盘容量
resize2fs 1.42.9 (28-Dec-2013)
Filesystem at /dev/vg-sdb/lv-sdb is mounted on /mnt/lv-sdb; on-line resizing required
old_desc_blocks = 2, new_desc_blocks = 3
The filesystem on /dev/vg-sdb/lv-sdb is now 5217280 blocks long.

[root@localhost ~]# df -Th    
Filesystem                  Type      Size  Used Avail Use% Mounted on
/dev/mapper/centos-root     xfs        95G   16G   80G  17% /
devtmpfs                    devtmpfs  979M     0  979M   0% /dev
tmpfs                       tmpfs     991M     0  991M   0% /dev/shm
tmpfs                       tmpfs     991M  9.6M  981M   1% /run
tmpfs                       tmpfs     991M     0  991M   0% /sys/fs/cgroup
/dev/sda1                   xfs      1014M  133M  882M  14% /boot
tmpfs                       tmpfs     199M     0  199M   0% /run/user/0
/dev/mapper/vg--sdb-lv--sdb ext4       20G   44M   19G   1% /mnt/lv-sdb   # lv逻辑卷扩容到19G了