1. Questions

I created a VMware virtual machine to install OpenStack Kolla. Since only 8G of space was allocated to the root directory when the virtual machine was created, it was obviously not enough for later use and I wanted to expand 10G of space.

View Current Disk

[root@kolla-queens ~]# fdisk -l

Disk /dev/sda: 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: 0x000d78d5

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1            2048    20971519    10484736   8e  Linux LVM
/dev/sda2        20971520    41943039    10485760   83  Linux

Disk /dev/mapper/centos-root: 8585 MB, 8585740288 bytes, 16769024 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
......

2. Solution

Since the /dev/sda1 partition is of type LVM, it can be extended

First, add a 10G hard drive to the virtual machine and restart it

You see that a disk/dev/sdb already exists, size 10.7 GB

[root@kolla-queens ~]# fdisk -l

Disk /dev/sda: 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: 0x000d78d5

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1            2048    20971519    10484736   8e  Linux LVM
/dev/sda2        20971520    41943039    10485760   83  Linux

Disk /dev/sdb: 10.7 GB, 10737418240 bytes, 20971520 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes

Disk /dev/mapper/centos-root: 8585 MB, 8585740288 bytes, 16769024 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
......

Create partition/dev/sdb, note that 8e is also the LVM type
#followed by my comment

[root@kolla-queens ~]# 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 0xf9d73537.

Command (m for help): n   # Enter command n to create a new partition
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p    # Enter p, or press Enter directly
Partition number (1-4, default 1): 1  # input 1，Or press Enter directly
First sector (2048-20971519, default 2048):   # Press Enter Directly
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-20971519, default 20971519):   # Press Enter Directly
Using default value 20971519
Partition 1 of type Linux and of size 10 GiB is set

Command (m for help): t  # Enter command t to define the type of new partition
Selected partition 1
Hex code (type L to list all codes): 8e # input 8e，8e yes Linux LVM Type Code
Changed type of partition 'Linux' to 'Linux LVM'

Command (m for help): w  # Enter command w to complete the modification
The partition table has been altered!

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

You see that partition/dev/sdb1 already exists

[root@kolla-queens ~]# fdisk -l

Disk /dev/sda: 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: 0x000d78d5

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1            2048    20971519    10484736   8e  Linux LVM
/dev/sda2        20971520    41943039    10485760   83  Linux

Disk /dev/sdb: 10.7 GB, 10737418240 bytes, 20971520 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: 0xf9d73537

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048    20971519    10484736   8e  Linux LVM

Disk /dev/mapper/centos-root: 8585 MB, 8585740288 bytes, 16769024 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
......

Create PV

[root@kolla-queens ~]# pvcreate /dev/sdb1
  Physical volume "/dev/sdb1" successfully created.

Look at the LV and show that the LV Path is/dev/centos/root and the VG Name is CentOS

[root@kolla-queens ~]# lvdisplay
......
     --- Logical volume ---
  LV Path                /dev/centos/root
  LV Name                root
  VG Name                centos
  LV UUID                eh3XHa-w5Hy-pbGA-qqbi-p4j6-H5Gl-LdBRlu
  LV Write Access        read/write
  LV Creation host, time localhost, 2016-09-13 23:42:05 +0800
  LV Status              available
  # open                 1
  LV Size                <8.00 GiB
  Current LE             2047
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:0

Extend VG centos

[root@kolla-queens ~]# vgextend centos /dev/sdb1
  Volume group "centos" successfully extended

Extend LV/dev/centos/root

[root@kolla-queens ~]# lvextend /dev/centos/root /dev/sdb1
  Size of logical volume centos/root changed from <8.00 GiB (2047 extents) to 17.99 GiB (4606 extents).
  Logical volume centos/root successfully resized.

If your system is using an XFS file system, you need to run the following commands:

xfs_growfs /dev/centos/root

If the system is not using an XFS file system, you need to run the following command:

resize2fs /dev/centos/root

I am the xfs file system
So run

[root@kolla-queens ~]# xfs_growfs /dev/centos/root
meta-data=/dev/mapper/centos-root isize=256    agcount=4, agsize=524032 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=0        finobt=0 spinodes=0
data     =                       bsize=4096   blocks=2096128, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=0
log      =internal               bsize=4096   blocks=2560, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 2096128 to 4716544

Viewing disk space information, /dev/mapper/centos-root has been expanded to 18G

[root@kolla-queens ~]# df -h
Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/centos-root   18G  2.0G   16G  12% /
devtmpfs                 3.9G     0  3.9G   0% /dev
tmpfs                    3.9G     0  3.9G   0% /dev/shm
tmpfs                    3.9G  8.7M  3.9G   1% /run
tmpfs                    3.9G     0  3.9G   0% /sys/fs/cgroup
tmpfs                    781M     0  781M   0% /run/user/0