如何安全的删除Linux LVM中的PV物理卷(硬盘或分区)

 　　情况介绍：,　　一、由于硬盘或者分区的操作方式其实都一样，所以我这里就以分区为例。,　　二、/home分区2.6G，由如下pv组成：,　　/dev/sda5 100M,　　/dev/sda6 200M,　　/dev/sda7 300M,　　/dev/sda8 400M,　　/dev/sda9 500M,　　/dev/sda10 600M,　　/dev/sda11 500M,　　很碎对吧?^_^因为测试。,　　三、随机写了一堆文件进去，用量达到了2G，空闲500M,　　四、准备将sda6这个200M的PV卸掉(卸掉的容量必须小于空闲容量),　　好了开始具体操作了。,　　卸载分区(缩小操作必须卸载才能进行)：,　　umount /home,　　缩小分区：,　　e2fsck -f /dev/liuhg_disk/home,　　resize2fs /dev/liuhg_disk/home 2200M,　　首先将分区缩小到2200M这是为了给sda6腾出空间，sda6为200M，而我腾出了400M，因此应该是足够的。,　　缩小逻辑卷：,　　lvreduce -L 2200M /dev/liuhg_disk/home,　　分区缩小了用到的逻辑卷也要随着缩小，并查看PV使用的状态：,　　pvdisplay -m,　　显示如下：,　　--- Physical volume ---,　　PV Name /dev/sda5,　　VG Name liuhg_disk,　　PV Size 103.26 MiB / not usable 3.26 MiB,　　Allocatable yes (but full),　　PE Size 4.00 MiB,　　Total PE 25,　　Free PE 0,　　Allocated PE 25,　　PV UUID 5lnx52-b4jc-OOfZ-f2QA-ttdQ-DZeD-Ce3rb3,　　--- Physical Segments ---,　　Physical extent 0 to 24:,　　Logical volume /dev/liuhg_disk/home,　　Logical extents 0 to 24,　　--- Physical volume ---,　　PV Name /dev/sda6,　　VG Name liuhg_disk,　　PV Size 203.92 MiB / not usable 3.92 MiB,　　Allocatable yes (but full),　　PE Size 4.00 MiB,　　Total PE 50,　　Free PE 0 <-----太悲剧了，sda6里写满了数据一点不剩,　　Allocated PE 50 <-----这50PE的数据要挪走才行，否则数据就丢了，并且存放的地方也必须是连续的至少50PE,　　PV UUID S2ane6-nlFG-uSNR-35NP-Yxa6-cXRb-r8E8mK,　　--- Physical Segments ---,　　Physical extent 0 to 49:,　　Logical volume /dev/liuhg_disk/home,　　Logical extents 25 to 74,　　--- Physical volume ---,　　PV Name /dev/sda7,　　VG Name liuhg_disk,　　PV Size 305.89 MiB / not usable 1.89 MiB,　　Allocatable yes,　　PE Size 4.00 MiB,　　Total PE 76,　　Free PE 76 <---这个分区有76个空余，因此预计装那50个是不会有问题的,　　Allocated PE 0,　　PV UUID 9CFnlx-CAEw-CSul-Rig9-FiCN-zK0a-oGmTEP,　　--- Physical Segments ---,　　Physical extent 0 to 75:,　　FREE,　　--- Physical volume ---,　　PV Name /dev/sda8,　　VG Name liuhg_disk,　　PV Size 407.87 MiB / not usable 3.87 MiB,　　Allocatable yes,　　PE Size 4.00 MiB,　　Total PE 101,　　Free PE 60,　　Allocated PE 41,　　PV UUID X0I8p0-x2xr-2xLG-QQD4-jbtS-3C4i-xPn4Bl,　　--- Physical Segments ---,　　Physical extent 0 to 40:,　　Logical volume /dev/liuhg_disk/home,　　Logical extents 471 to 511,　　Physical extent 41 to 100:,　　FREE,　　--- Physical volume ---,　　PV Name /dev/sda9,　　VG Name liuhg_disk,　　PV Size 509.84 MiB / not usable 1.84 MiB,　　Allocatable yes (but full),　　PE Size 4.00 MiB,　　Total PE 127,　　Free PE 0,　　Allocated PE 127,　　PV UUID avJQaA-oMKt-NEoJ-ojBK-2Csc-1dca-1mh6Ue,　　--- Physical Segments ---,　　Physical extent 0 to 126:,　　Logical volume /dev/liuhg_disk/home,　　Logical extents 225 to 351,　　--- Physical volume ---,　　PV Name /dev/sda10,　　VG Name liuhg_disk,　　PV Size 603.98 MiB / not usable 3.98 MiB,　　Allocatable yes (but full),　　PE Size 4.00 MiB,　　Total PE 150,　　Free PE 0,　　Allocated PE 150,　　PV UUID JlMIAF-A49n-M6HA-ZLXf-d8nS-pfZr-YeQsKT,　　--- Physical Segments ---,　　Physical extent 0 to 149:,　　Logical volume /dev/liuhg_disk/home,　　Logical extents 75 to 224,　　--- Physical volume ---,　　PV Name /dev/sda11,　　VG Name liuhg_disk,　　PV Size 478.47 MiB / not usable 2.47 MiB,　　Allocatable yes (but full),　　PE Size 4.00 MiB,　　Total PE 119,　　Free PE 0,　　Allocated PE 119,　　PV UUID xnHJNA-tDVx-dryX-KM1x-g96Y-sptI-9iUOcU,　　--- Physical Segments ---,　　Physical extent 0 to 118:,　　Logical volume /dev/liuhg_disk/home,　　Logical extents 352 to 470,　　将sda6设置为离线状态：,　　pvchange -xn /dev/sda6,　　使用pvdisplay -m,　　显示如下：,　　……,　　--- Physical volume ---,　　PV Name /dev/sda6,　　VG Name liuhg_disk,　　PV Size 203.92 MiB / not usable 3.92 MiB,　　Allocatable NO <-----表示已经关闭了该PV,　　PE Size 4.00 MiB,　　Total PE 50,　　Free PE 0,　　Allocated PE 50,　　PV UUID S2ane6-nlFG-uSNR-35NP-Yxa6-cXRb-r8E8mK,　　……,　　将sda6的数据移走：,　　pvmove -i 1 /dev/sda6,　　-i 1是每1秒钟报告一次数据迁移的进度。,　　[root@liuhg /]# pvmove -i 1 /dev/sda6,　　/dev/sda6: Moved: 38.0%,　　/dev/sda6: Moved: 84.0%,　　/dev/sda6: Moved: 100.0%,　　重新用pvdisplay -m,　　显示如下：,　　……,　　--- Physical volume ---,　　PV Name /dev/sda6,　　VG Name liuhg_disk,　　PV Size 203.92 MiB / not usable 3.92 MiB,　　Allocatable NO,　　PE Size 4.00 MiB,　　Total PE 50,　　Free PE 50 <----显示完全空闲和Total PE数一致,　　Allocated PE 0,　　PV UUID S2ane6-nlFG-uSNR-35NP-Yxa6-cXRb-r8E8mK,　　……,　　从卷组里把sda6删除:,　　[root@liuhg /]# vgreduce liuhg_disk /dev/sda6,　　Removed "/dev/sda6" from volume group "liuhg_disk",　　pvdisplay -m再看看吧：,　　--- NEW Physical volume --- <-----还告诉你这是一个新的PV ^_^,　　PV Name /dev/sda6,　　VG Name <-----空了,　　PV Size 203.92 MiB,　　Allocatable NO,　　PE Size 0,　　Total PE 0,　　Free PE 0,　　Allocated PE 0,　　PV UUID S2ane6-nlFG-uSNR-35NP-Yxa6-cXRb-r8E8mK,　　到此vgdisplay -v能看到已经没有了/dev/sda6了。重新挂载/home,　　[root@liuhg /]# mount /dev/liuhg_disk/home /home,　　[root@liuhg /]# df -h,　　Filesystem Size Used Avail Use% Mounted on,　　/dev/sda1 2.0G 546M 1.3G 30% /,　　tmpfs 504M 0 504M 0% /dev/shm,　　/dev/mapper/liuhg_disk-home,　　2.2G 1.8G 42M 98% /home,　　进去看看数据，一个都没丢。,