一直都说LVM可以在线增加空间，一直都没有试过
下面小试一下：
1.增加硬盘
2.创建PV
3.添加PV到VG
4.扩展LV
1.增加硬盘
该干嘛干嘛
添加后需要重启（有知道不用重启的办法吗）
--这个是新添加的硬盘 [root@localhost ~]# fdisk -l /dev/sdb Disk /dev/sdb: 5368 MB, 5368709120 bytes 255 heads, 63 sectors/track, 652 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk /dev/sdb doesn't contain a valid partition table
2.创建PV
--命令很简单
--命令很简单 [root@localhost ~]# pvcreate /dev/sdb Physical volume "/dev/sdb" successfully created --可以看到新的PV了 [root@localhost ~]# pvdisplay /dev/hdc: open failed: No medium found --- Physical volume --- PV Name /dev/sda2 VG Name VolGroup00 PV Size 9.90 GB / not usable 22.76 MB Allocatable yes (but full) PE Size (KByte) 32768 Total PE 316 Free PE 0 Allocated PE 316 PV UUID n5fS6M-jBiH-n9vU-pBTd-iOCv-BbTe-BUeNZo "/dev/sdb" is a new physical volume of "5.00 GB" --- NEW Physical volume --- PV Name /dev/sdb VG Name PV Size 5.00 GB Allocatable NO PE Size (KByte) 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID TDs3mN-3ON3-eHbl-cohr-7Hr3-8608-jiLlXG
3.添加PV到VG
--指定对应的VG和PV [root@localhost ~]# vgextend VolGroup00 /dev/sdb Volume group "VolGroup00" successfully extended --看到新的5G添加到VG里面了，状态是没有分配 [root@localhost ~]# vgdisplay --- Volume group --- VG Name VolGroup00 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 14.84 GB PE Size 32.00 MB Total PE 475 Alloc PE / Size 316 / 9.88 GB Free PE / Size 159 / 4.97 GB VG UUID x1uyPD-qBgE-2yQV-T1Cb-IGIz-e4LB-fghf1W
4.扩展LV
--先添加2G练手 [root@localhost ~]# lvextend -L +2G /dev/VolGroup00/LogVol00 Extending logical volume LogVol00 to 10.88 GB Logical volume LogVol00 successfully resized --成功后还未看到新的空间 [root@localhost ~]# df -m Filesystem 1M-blocks Used Available Use% Mounted on /dev/mapper/VolGroup00-LogVol00 8804 7362 988 89% / --需要手动刷新 [root@localhost ~]# resize2fs /dev/VolGroup00/LogVol00 resize2fs 1.39 (29-May-2006) Filesystem at /dev/VolGroup00/LogVol00 is mounted on /; on-line resizing required Performing an on-line resize of /dev/VolGroup00/LogVol00 to 2850816 (4k) blocks. The filesystem on /dev/VolGroup00/LogVol00 is now 2850816 blocks long. --现在就完成了 [root@localhost ~]# df -m Filesystem 1M-blocks Used Available Use% Mounted on /dev/mapper/VolGroup00-LogVol00 10788 7365 2867 72% /
若需要先缩小则使用以下命令：
lvreduce -L -20G /dev/mapper/vg_mysvr-lv_home
resize2fs /dev/mapper/vg_my-lv_home
lvextend -L +20G /dev/mapper/vg_mysvr-lv_root
resize2fs /dev/mapper/vg_mysvr-lv_root