[root@docker1 ~]# vgdisplay
--- Volume group ---
VG Name cl
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 5
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 38.99 GiB
PE Size 4.00 MiB
Total PE 9982
Alloc PE / Size 5376 / 21.00 GiB
Free PE / Size 4606 / 17.99 GiB
VG UUID 0g6KUL-2kdC-e4Ml-EMFH-2JYs-SNUT-bn09Od
[root@docker1 ~]# lvextend -L 17G /dev/mapper/cl-root
New size given (4352 extents) not larger than existing size (5120 extents)
[root@docker1 ~]# lvextend -L 16G /dev/mapper/cl-root
New size given (4096 extents) not larger than existing size (5120 extents)
给lvm---根目录/dev/centos/cl-root扩容
[root@docker1 ~]# lvextend -l +100%FREE /dev/mapper/cl-root
Size of logical volume cl/root changed from 20.00 GiB (5120 extents) to 37.99 GiB (9726 extents).
Logical volume cl/root successfully resized.
LVM报错:New size given (4096 extents) not larger
原文：http://blog.51cto.com/sf1314/2062126