1，创建分区
[root@host-10-158-172-44 ~]# fdisk /dev/vda
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
Partition type:
p primary (2 primary, 0 extended, 2 free)
e extended
Select (default p): Enter
Partition number (3,4, default 3): Enter
First sector (41943040-83886079, default 41943040): Enter
Using default value 41943040
Last sector, +sectors or +size{K,M,G} (41943040-83886079, default 83886079):
Using default value 83886079
Partition 3 of type Linux and of size 20 GiB is set
Command (m for help): t
Partition number (1-3, default 3): Enter
Hex code (type L to list all codes): 8e
Changed type of partition 'Linux' to 'Linux LVM'
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
[root@host-10-158-172-44 ~]# fdisk -l
Disk /dev/vda: 42.9 GB, 42949672960 bytes, 83886080 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: 0x0009b56e
Device Boot Start End Blocks Id System
/dev/vda1 * 2048 1026047 512000 83 Linux
/dev/vda2 1026048 41943039 20458496 8e Linux LVM
/dev/vda3 41943040 83886079 20971520 8e Linux LVM
Disk /dev/mapper/centos-root: 18.8 GB, 18756927488 bytes, 36634624 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-swap: 2147 MB, 2147483648 bytes, 4194304 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，创建PV
[root@host-10-158-172-44 ~]# partprobe #使分区表生效，无需重启
[root@host-10-158-172-44 ~]# pvcreate /dev/vda3 #使用pvcreate转换
WARNING: dos signature detected on /dev/vda3 at offset 510. Wipe it? [y/n]: y
Wiping dos signature on /dev/vda3.
Physical volume "/dev/vda3" successfully created
[root@host-10-158-172-44 ~]# pvdisplay #查看已经存在的pv
--- Physical volume ---
PV Name /dev/vda2
VG Name centos
PV Size 19.51 GiB / not usable 3.00 MiB
Allocatable yes
PE Size 4.00 MiB
Total PE 4994
Free PE 10
Allocated PE 4984
PV UUID 2MR7wz-fh1t-6nlO-glse-MEBz-8Rjo-Y7gkhI
"/dev/vda3" is a new physical volume of "20.00 GiB"
--- NEW Physical volume ---
PV Name /dev/vda3
VG Name
PV Size 20.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID dvb6J8-YszL-KP8x-LDHc-RGwT-pB3u-s19Pe9
3，扩展VG
[root@host-10-158-172-44 ~]# vgextend centos /dev/vda3
Volume group "centos" successfully extended
[root@host-10-158-172-44 ~]# vgdisplay #查看已经存在的vg
--- Volume group ---
VG Name centos
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 4
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 2
Open LV 2
Max PV 0
Cur PV 2
Act PV 2
VG Size 39.50 GiB
PE Size 4.00 MiB
Total PE 10113
Alloc PE / Size 4984 / 19.47 GiB
Free PE / Size 5129 / 20.04 GiB
VG UUID h5CW2E-aYjt-AZLN-CTMe-7lZp-e2xk-yuDnLs
4，扩展LV
[root@host-10-158-172-44 ~]# lvdisplay #查看已经存在的lv
--- Logical volume ---
LV Path /dev/centos/swap
LV Name swap
VG Name centos
LV UUID U0ANhF-afAc-pb0U-AYmN-EJH0-Wyj8-H2bvws
LV Write Access read/write
LV Creation host, time localhost, 2015-12-01 21:35:58 +0800
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/centos/root
LV Name root
VG Name centos
LV UUID sG5AuB-SsYW-ggN5-tl6l-csEg-14F7-6NNVnO
LV Write Access read/write
LV Creation host, time localhost, 2015-12-01 21:35:59 +0800
LV Status available
# open 1
LV Size 17.47 GiB
Current LE 4472
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
[root@host-10-158-172-44 ~]# lvextend -L 37G /dev/centos/root #扩展lv
Size of logical volume centos/root changed from 20.00 GiB (5120 extents) to 37.00 GiB (9472 extents).
Logical volume root successfully resized
注：lvextend -r -l +100%FREE /dev/centos/root #可使用此命令将所有的vg全部分配
5，执行重设大小
[root@host-10-158-172-44 ~]# xfs_growfs /dev/mapper/centos-root #重设大小
meta-data=/dev/mapper/centos-root isize=256 agcount=5, agsize=1144832 blks
= sectsz=512 attr=2, projid32bit=1
= crc=0 finobt=0
data = bsize=4096 blocks=5242880, 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 5242880 to 9699328
[root@host-10-158-172-44 ~]# df -h #查看
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 37G 789M 37G 3% /
devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs 1.9G 0 1.9G 0% /dev/shm
tmpfs 1.9G 8.4M 1.9G 1% /run
tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/vda1 497M 120M 378M 25% /boot