問題描述：掛載點 “/dev/xx” 的使用率達100%，空間不夠，所以要對其進行分區。
解決：
1、通過vmware、vsphere等虛擬機設置，調整增大磁盤空間
2、輸入命令： fdisk -l 查看現有情況
3、增加分區
$> fdisk /dev/sda
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
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
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)
Command (m for help): n
Command action
e extended
p primary partition (1-4)
輸入p，默認回車，然後w退出。
4、創建、查詢物理卷
$> pvcreate /dev/sda4
dev_is_mpath: failed to get device for 8:4
Physical volume "/dev/sda4" successfully created
$> vgscan
Reading all physical volumes. This may take a while...
Found volume group "vg_root" using metadata type lvm2
5、新增物理卷擴展，“vg_root”
$> vgextend vg_sddb02 /dev/sda4
Volume group "vg_root" successfully extended
$> lvextend -L +1024G /dev/vg_root
Extending logical volume lv_root to 1.48 TiB
Logical volume lv_root successfully resized
6、執行重設
$> resize2fs /dev/vg_root
resize2fs 1.41.12 (17-May-2010)
Filesystem at /dev/vg_root is mounted on /; on-line resizing required
old desc_blocks = 31, new_desc_blocks = 95
Performing an on-line resize of /dev/vg_root to 396230656 (4k) blocks.
The filesystem on /dev/vg_root is now 396230656 blocks long.
7、成功，輸入命令 df -lh 查看
