LVM在线更换物理硬盘
前提：硬盘支持热插拔，操作系统内核支持硬盘的热插拔
本文利用系统已经存在的空闲硬盘，替换正在跑系统的分区。
查看原来的物理卷情况：
# pvs PV VG Fmt Attr PSize PFree /dev/sda2 VolGroup lvm2 a- 15.51g 0
将sdb加入到逻辑卷中
# pvcreate /dev/sdb Physical volume "/dev/sdb" successfully created # vgextend VolGroup /dev/sdb Volume group "VolGroup" successfully extended
查看pv状态
# pvdisplay --- Physical volume --- PV Name /dev/sda2 VG Name VolGroup PV Size 15.51 GiB / not usable 3.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 3970 Free PE 0 Allocated PE 3970 PV UUID qkhe8I-Ro1L-K1Df-hUKf-6j8O-kdV0-5t26Tc --- Physical volume --- PV Name /dev/sdb VG Name VolGroup PV Size 16.00 GiB / not usable 4.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 4095 Free PE 4095 Allocated PE 0 PV UUID GJkAN4-yLCW-aduY-7PDc-3fC0-V7tf-pCcf3u
开始迁移数据，这将是个漫长的等待过程。
# pvmove /dev/sda2 /dev/sda2: Moved: 0.0% /dev/sda2: Moved: 1.4% ..... /dev/sda2: Moved: 100.0%
可以移除原来那块硬盘（分区）了
# vgreduce VolGroup /dev/sda2 Removed "/dev/sda2" from volume group "VolGroup"
将闲置硬盘（分区）从pv中删除
# pvremove /dev/sda2 Labels on physical volume "/dev/sda2" successfully wiped
整个过程就完毕了。