买了个KT服务器，KT官方技术只给/home分了2G，也是醉了。教程参考http://jingyan.baidu.com/article/6079ad0e9d7d9e28fe86db11.html
创建PV:
扫面系统PV：pvscan
查看PV：pvdisplay
[root@DQ5620-C5-4-SAS ~]# pvscan
PV /dev/sda2 VG rootvg lvm2 [464.47 GiB / 425.47 GiB free]
Total: 1 [464.47 GiB] / in use: 1 [464.47 GiB] / in no VG: 0 [0 ]
[root@DQ5620-C5-4-SAS ~]# pvdisplay
— Physical volume —
PV Name /dev/sda2
VG Name rootvg
PV Size 464.48 GiB / not usable 16.00 MiB
Allocatable yes
PE Size 32.00 MiB
Total PE 14863
Free PE 13615
Allocated PE 1248
PV UUID pU8XYG-Au6O-vNrY-CMMa-2dzD-MuVP-ywykAh