lvm_reduce---lvextend

场景:data减少20G，home增容20G
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1.umount /dev/mapper/VGygz-lvdata_HDD
2.e2fsck -f /dev/mapper/VGygz-lvdata_HDD
3.resize2fs /dev/mapper/VGygz-lvdata_HDD  1024G
4.lvreduce -L 1024G /dev/mapper/VGygz-lvdata_HDD
5.resize2fs /dev/mapper/VGygz-lvdata_HDD
6.mount -a
7.df -Th
8.lvextend -l +100%FREE /dev/mapper/VGygz-lvhome
9.resize2fs /dev/mapper/VGygz-lvhome
10.df -Th