This is more of Resize LVM
I have tested this on CentOS 5.5. Since this is root partition modification, I’ll recommend to keep config backup before proceeding.

create new partition (partition id should be 8e Linux LVM)
ADD PHYSICAL VOLUME

pvcreate /dev/new_partition

Verify new physical volume

pvdisplay
Or
pvscan

Extend existing VOLUME GROUP

vgextend VolGroup00 /dev/xvda3

make sure vg free size is = new partition size using vgdisplay command
Extend existing LVM by adding new partition

lvextend /dev/VolGroup00/LogVol00 /dev/xvda3

make sure lv size is increased, use lvdisplay

RESIZE FILE SYSTEM
Reboot Linux to init1

umount /dev/VolGroup00/LogVol00
fsck -f /dev/VolGroup00/LogVol00

Mount / partition or reboot to init1 for following command to run.

resize2fs /dev/VolGroup00/LogVol00

Now you may reboot & check / partition size.

LVM Resize root partition -Centos is a post from: LinuxReaders

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Here We are sharing guide to resize LVM size.

create new partition (partition id should be 8e Linux LVM)

ADD PHYSICAL VOLUME

pvcreate /dev/new_partition

Verify new physical volume

pvdisplay
Or
pvscan

Extend existing VOLUME GROUP

vgextend VolGroup00 /dev/xvda3

make sure vg free size is = new partition size using vgdisplay command

Extend existing LVM by adding new partition

lvextend /dev/VolGroup00/LogVol00 /dev/xvda3

make sure lv size is increased, use lvdisplay

RESIZE FILE SYSTEM

umount /dev/VolGroup00/LogVol00

fsck -f /dev/VolGroup00/LogVol00

resize2fs /dev/VolGroup00/LogVol00

Resize LVM -Centos is a post from: LinuxReaders

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