准备

vmware安装centos7，在lvm下和非lvm下分别进行测试

虚拟机扩展硬盘容量

选择扩展将原来的20g扩展到100g

非lvm下如何扩展磁盘

fdisk -l发现只有一个盘/dev/sda，分成了3个区，sda1,sda2,sda3

Disk /dev/sda: 20.4 GB
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: 0x000bbf20

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048      616447      307200   83  Linux
/dev/sda2          616448     4810751     2097152   82  Linux swap / Solaris
/dev/sda3         4810752    41943039    18566144   83  Linux

开始分区

[root@promote ~]# fdisk /dev/sda
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.


Command (m for help): m
Command action
   a   toggle a bootable flag
   b   edit bsd disklabel
   c   toggle the dos compatibility flag
   d   delete a partition
   g   create a new empty GPT partition table
   G   create an IRIX (SGI) partition table
   l   list known partition types
   m   print this menu
   n   add a new partition
   o   create a new empty DOS partition table
   p   print the partition table
   q   quit without saving changes
   s   create a new empty Sun disklabel
   t   change a partition's system id
   u   change display/entry units
   v   verify the partition table
   w   write table to disk and exit
   x   extra functionality (experts only)

输入n 新建分区；
然后输入p，新建主分区；
输入分区编号4（已经有1，2，3了，所以新建的是4）；
之后一直按enter键，设置新建分区默认大小；
最后输入w 保存。

同步分区

partprobe
如果没有这一步，后面的格式化会提示下面错误

/dev/sda4: No such file or directory

格式化

mkfs.xfs /dev/sda4

挂载目录

[root@promote home]# mkdir /sda4
[root@promote home]# mount /dev/sda4 /sda4

新创建的分区不能开机自动挂载，每次重启机器都要手动挂载。
设置开机自动挂载需要修改/etc/fstab文件
cat /etc/fstab

UUID=6ead5f9b-3451-499c-947a-08e2dc947304 /                       xfs     defaults        0 0
UUID=d5ba0def-f729-4180-b7ff-584396e36bc0 /boot                   xfs     defaults        0 0
UUID=6f708491-e4b1-44ea-bd4b-d33876fa650c swap                    swap    defaults        0 0

查看分区uuid

[root@promote ~]# blkid /dev/sda4
/dev/sda4: UUID="818f6627-a91a-459c-aacb-220929178ba5" TYPE="xfs" 

在文件的最后增加一行
UUID=818f6627-a91a-459c-aacb-220929178ba5 /sda4 xfs defaults 0 0

验证

[root@promote ~]# df -Th
Filesystem     Type      Size  Used Avail Use% Mounted on
/dev/sda3      xfs        18G  8.0G  9.8G  45% /
devtmpfs       devtmpfs  970M     0  970M   0% /dev
tmpfs          tmpfs     984M  160K  984M   1% /dev/shm
tmpfs          tmpfs     984M  9.0M  975M   1% /run
tmpfs          tmpfs     984M     0  984M   0% /sys/fs/cgroup
/dev/sda4      xfs        80G   33M   80G   1% /sda4
/dev/sda1      xfs       297M  152M  146M  51% /boot
tmpfs          tmpfs     197M  8.0K  197M   1% /run/user/42
tmpfs          tmpfs     197M  8.0K  197M   1% /run/user/0

看到sda4为80g，恭喜自己成功了。

lvm下如何扩展磁盘

开始分区

注意类型是8e的

[root@promote qiu]# fdisk /dev/sda
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.


Command (m for help): n        新建
Partition type:            
   p   primary (2 primary, 0 extended, 2 free)
   e   extended
Select (default p): p          主分区
Partition number (3,4, default 3): 3   分区编码
First sector (41943040-209715199, default 41943040):  回车键默认扇区大小
Using default value 41943040
Last sector, +sectors or +size{K,M,G} (41943040-209715199, default 209715199): 回车键默认扇区大小
Using default value 209715199
Partition 3 of type Linux and of size 80 GiB is set

Command (m for help): t   修改分区类型
Partition number (1-3, default 3): 3  修改指定分区
Hex code (type L to list all codes): 8e  
Changed type of partition 'Linux' to 'Linux LVM'
Command (m for help): w

同步分区
partprobe
格式化
mkfs.xfs /dev/sda3

创建pv

pvcreate /dev/sda3

加入vg

vgextend cl /dev/sda3

扩展逻辑卷大小

[root@promote qiu]# lvdisplay
  --- Logical volume ---
  LV Path                /dev/cl/swap
  LV Name                swap
  VG Name                cl
  LV UUID                LRdTFN-ALQF-YZ2D-Ayj1-Mati-bY5H-meOPcv
  LV Write Access        read/write
  LV Creation host, time localhost.localdomain, 2018-06-30 07:00:29 -0700
  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/cl/root
  LV Name                root
  VG Name                cl
  LV UUID                u2AL50-gvWQ-OLsx-Lpc6-Z0g0-gPLL-VT6Jxm
  LV Write Access        read/write
  LV Creation host, time localhost.localdomain, 2018-06-30 07:00:30 -0700
  LV Status              available
  # open                 1
  LV Size                80.00 GiB
  Current LE             20480
  Segments               2
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:0

lvextend -L 80g /dev/cl/root 扩展到80g

同步文件系统

xfs_growfs /dev/cl/root

验证

[root@promote qiu]# df -Th
Filesystem          Type      Size  Used Avail Use% Mounted on
/dev/mapper/cl-root xfs        80G  4.7G   76G   6% /
devtmpfs            devtmpfs  969M     0  969M   0% /dev
tmpfs               tmpfs     984M  144K  984M   1% /dev/shm
tmpfs               tmpfs     984M  9.0M  975M   1% /run
tmpfs               tmpfs     984M     0  984M   0% /sys/fs/cgroup
/dev/sda1           xfs      1014M  173M  842M  18% /boot
tmpfs               tmpfs     197M   16K  197M   1% /run/user/0

看到root逻辑卷大小为80g，恭喜自己成功了。

其他

删除分区

[root@promote qiu]# fdisk /dev/sda
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.

Command (m for help): d
Partition number (1-3, default 3): 3
Partition 3 is deleted

Command (m for help): w

查看分区

Command (m for help): p

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: 0x000c58a8

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048     2099199     1048576   83  Linux
/dev/sda2         2099200    41943039    19921920   8e  Linux LVM