LVM实现动态扩容

LVM是逻辑盘卷管理（Logical VolumeManager）的简称，它是Linux环境下对磁盘分区进行管理的一种机制，LVM是建立在硬盘和分区之上的一个逻辑层，来提高磁盘分区管理的灵活性。通过LVM系统管理员可以轻松管理磁盘分区，如：将若干个磁盘分区连接为一个整块的卷组（volumegroup），形成一个存储池。管理员可以在卷组上随意创建逻辑卷组（logicalvolumes），并进一步在逻辑卷组上创建文件系统。管理员通过LVM可以方便的调整存储卷组的大小，并且可以对磁盘存储按照组的方式进行命名、管理和分配

查看磁盘空间

[root@ywcsb ~]# fdisk -l

Disk /dev/sda: 107.4 GB, 107374182400 bytes, 209715200 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: 0x000b7e20

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048     2099199     1048576   83  Linux
/dev/sda2         2099200   209715199   103808000   8e  Linux LVM

Disk /dev/sdb: 966.4 GB, 966367641600 bytes, 1887436800 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 /dev/mapper/centos_bgd--ngnix1-root: 102.1 GB, 102131302400 bytes, 199475200 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 /dev/mapper/centos_bgd--ngnix1-swap: 4160 MB, 4160749568 bytes, 8126464 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

创建物理卷

[root@ywcsb ~]# pvcreate /dev/sdb
  Physical volume "/dev/sdb" successfully created.

查看物理卷

 [root@ywcsb ~]# pvdisplay 
 --- Physical volume ---
  PV Name               /dev/sda2
  VG Name               centos_bgd-ngnix1
  PV Size               <99.00 GiB / not usable 3.00 MiB
  Allocatable           yes 
  PE Size               4.00 MiB
  Total PE              25343
  Free PE               1
  Allocated PE          25342
  PV UUID               vr9DRr-mwG8-89Vm-LmoV-Bqel-Ykga-HM5HLg

  "/dev/sdb" is a new physical volume of "900.00 GiB"
  --- NEW Physical volume ---
  PV Name               /dev/sdb
  VG Name               
  PV Size               900.00 GiB
  Allocatable           NO
  PE Size               0   
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               fhbfRd-x6qx-KVCd-3SBF-5lXN-Z81W-SIrRQz

查看当前卷组

  [root@ywcsb ~]# vgdisplay 
  --- Volume group ---
  VG Name               centos_bgd-ngnix1
  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       25342 / 98.99 GiB
  Free  PE / Size       1 / 4.00 MiB
  VG UUID               BFGY1M-PHqr-RBnE-87t2-bhYC-n7PX-idg4R1

扩展卷组，将/dev/sdb物理卷加到VG中

  [root@ywcsb ~]# vgextend centos_bgd-ngnix1 /dev/sdb
  Volume group "centos_bgd-ngnix1" successfully extended

查看逻辑卷

  [root@ywcsb ~]# lvdisplay 
  --- Logical volume ---
  LV Path                /dev/centos_bgd-ngnix1/root
  LV Name                root
  VG Name                centos_bgd-ngnix1
  LV UUID                2SnPdf-1zdM-lM5G-4fJz-oGve-JC2Z-fkTGUL
  LV Write Access        read/write
  LV Creation host, time bgd-ngnix1, 2018-11-21 13:08:20 +0800
  LV Status              available
  # open                 1
  LV Size                <95.12 GiB
  Current LE             24350
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:0

  --- Logical volume ---
  LV Path                /dev/centos_bgd-ngnix1/swap
  LV Name                swap
  VG Name                centos_bgd-ngnix1
  LV UUID                l8jyte-4j0X-00Am-ich0-9qen-QLaW-LWTSHI
  LV Write Access        read/write
  LV Creation host, time bgd-ngnix1, 2018-11-21 13:08:21 +0800
  LV Status              available
  # open                 2
  LV Size                <3.88 GiB
  Current LE             992
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:1

将VG空间划分到LV

  [root@ywcsb ~]# lvextend -l +100%FREE /dev/centos_bgd-ngnix1/root
  Size of logical volume centos_bgd-ngnix1/root changed from <95.12 GiB (24350 extents) to <995.12 GiB (254750 extents).
  Logical volume centos_bgd-ngnix1/root successfully resized.
  # 或者只添加100G
  [root@ywcsb ~]# lvextend -L 100G /dev/centos_bgd-ngnix1/root

重定义空间大小

  [root@bgd-mysql3 ~]# resize2fs  /dev/centos_bgd-ngnix1/root
meta-data=/dev/mapper/centos_bgd--ngnix1-root isize=512    agcount=4, resize2fs 1.42.13 (17-May-2015)
Filesystem at /dev/ubuntu-vg/root is mounted on /; on-line resizing required
old_desc_blocks = 7, new_desc_blocks = 13
The filesystem on /dev/ubuntu-vg/root is now 51989504 (4k) blocks long.
# 或者使用xfs_growfs 
[root@ywcsb ~]#xfs_growfs   /dev/centos_bgd-ngnix1/root