VDI size increase not reflecting

Question

I have a dynamically allocated virtual disk, which was initially 40GB.

I increased the disk size from 40 GB to 100GB first and then also updated the partition using GParted as described here, https://www.rootusers.com/use-gparted-to-increase-disk-size-of-a-linux-native-partition/

But still the disk size does not update, df -h shows

Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/I0--vg-root   35G   33G  1.3M 100% /
none                     4.0K     0  4.0K   0% /sys/fs/cgroup
udev                     2.4G  4.0K  2.4G   1% /dev
tmpfs                    485M  564K  484M   1% /run
none                     5.0M     0  5.0M   0% /run/lock
none                     2.4G  4.0K  2.4G   1% /run/shm
none                     100M     0  100M   0% /run/user
/dev/sda1                236M   44M  180M  20% /boot
/home/iadm/.Private     35G   33G  1.3M 100% /home/iadm

Answer 1

You forgot to resize the filesystem.

See

man resize2fs (for ext4)

or

man btrfs-filesystem (for btrfs).

Answer 2

The root partition is on an LVM logical volume (LV) named root in a volume group (VG) named I0-vg, so you must first expand the underlying physical volume (PV), then expand the LV, then expand the filesystem:

pvresize /dev/<pv_dev>
lvresize --extents +100%FREE I0-vg/root
resize2fs /dev/mapper/I0--vg-root

where <pv_dev> is the block device of your LVM PV.