0、结果验证
扩容前
扩容后
1、创建分区
[root@localhost ~]# parted -s /dev/sdb mklabel gpt
[root@localhost ~]# parted -s /dev/sdb mkpart logic 0% 100%
[root@localhost ~]#
[root@localhost ~]#
[root@localhost ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 25G 0 disk
├─sda1 8:1 0 1G 0 part /boot
└─sda2 8:2 0 24G 0 part
├─centos-root 253:0 0 21.5G 0 lvm /
└─centos-swap 253:1 0 2.5G 0 lvm [SWAP]
sdb 8:16 0 20G 0 disk
└─sdb1 8:17 0 20G 0 part
sr0 11:0 1 4.2G 0 rom
2、创建物理机（PV）
[root@localhost ~]# pvcreate /dev/sdb1
Physical volume "/dev/sdb1" successfully created.
3、查看PV是否创建成功
可以看见/dev/sdb1的pv已创建成功，且系统根目录所属PV是/dev/sda2，VG是centos
[root@localhost ~]# pvdisplay
--- Physical volume ---
PV Name /dev/sda2
VG Name centos
PV Size <24.00 GiB / not usable 3.00 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 6143
Free PE 0
Allocated PE 6143
PV UUID wC0d22-e0im-Uh91-o8Ac-Gvxv-Y5Wu-YFXvv9
"/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 Gd4MdO-YRoV-dfdc-ZrUB-raJq-zZHA-YaWMD0
4、扩容卷组（VG）
将新的PV（/dev/sdb1）添加到当前根目录所属VG（centos）中
[root@localhost ~]# vgextend centos /dev/sdb1
Volume group "centos" successfully extended
可以看到我们新增的PV（/dev/sdb1）的VG已被改成centos
[root@localhost ~]# pvdisplay
--- Physical volume ---
PV Name /dev/sda2
VG Name centos
PV Size <24.00 GiB / not usable 3.00 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 6143
Free PE 0
Allocated PE 6143
PV UUID wC0d22-e0im-Uh91-o8Ac-Gvxv-Y5Wu-YFXvv9
--- Physical volume ---
PV Name /dev/sdb1
VG Name centos
PV Size <20.00 GiB / not usable 2.00 MiB
Allocatable yes
PE Size 4.00 MiB
Total PE 5119
Free PE 5119
Allocated PE 0
PV UUID Gd4MdO-YRoV-dfdc-ZrUB-raJq-zZHA-YaWMD0
5、扩展逻辑卷（LV）
可以看出当前卷组VG(centos)中存在两个逻辑卷LV(swap、root),其中swap作为虚拟内存使用，root是我们本次需要扩展的系统根目录所在的逻辑卷
[root@localhost ~]# lvdisplay
--- Logical volume ---
LV Path /dev/centos/swap
LV Name swap
VG Name centos
LV UUID ffr8Aq-yaiS-chiR-A7Eo-hKBI-uo2D-aWAkLT
LV Write Access read/write
LV Creation host, time localhost, 2018-05-22 07:14:32 +0800
LV Status available
# open 2
LV Size 2.50 GiB
Current LE 640
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 0RhsLO-eA0B-Vd7g-gxGp-nhp0-f1l3-XxohXu
LV Write Access read/write
LV Creation host, time localhost, 2018-05-22 07:14:32 +0800
LV Status available
# open 1
LV Size <21.50 GiB
Current LE 5503
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
6、扩展逻辑卷
由于前面操作已经将新的磁盘空间分区并划分给了我们系统所在的卷组VG(centos)，所以现在需要对该卷组的可用容量进行分配，以下命令将centos卷组的所有剩余空间分配给逻辑卷root
[root@localhost ~]# lvextend -l +100%FREE /dev/centos/root
Size of logical volume centos/root changed from <21.50 GiB (5503 extents) to 41.49 GiB (10622 e
xtents). Logical volume centos/root successfully resized.
7、扩展文件系统
[root@localhost ~]# xfs_growfs /dev/centos/root
meta-data=/dev/mapper/centos-root isize=512 agcount=4, agsize=1408768 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0 spinodes=0
data = bsize=4096 blocks=5635072, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal bsize=4096 blocks=2751, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 5635072 to 10876928
[root@localhost ~]# df -HT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/centos-root xfs 45G 1.7G 43G 4% /
devtmpfs devtmpfs 2.0G 0 2.0G 0% /dev
tmpfs tmpfs 2.0G 0 2.0G 0% /dev/shm
tmpfs tmpfs 2.0G 13M 2.0G 1% /run
tmpfs tmpfs 2.0G 0 2.0G 0% /sys/fs/cgroup
/dev/sda1 xfs 1.1G 149M 915M 14% /boot
tmpfs tmpfs 396M 0 396M 0% /run/user/0
