must be the last partition on disk, this is usefull for those huge non-lvm virtual machines that you add storage to later on

Resize a Linux filesystem without LVM

1. boot up a linux live if you want to resize the root partition
2. follow below:
  Run fdisk on the right disk (X is the correct letter of your disk): fdisk /dev/sdX
  Check the partition table by pressing p (to view partition details)
  Delete the partition by pressing d (to delete the partition)
  Select the right partition that you want to delete, in most cases will be the only on the disk, so press 1 (to select the partition)
  Create a new partition by pressing n (to create a new partition) and select the partition type whether Primary (by pressing p) and the right number
  Get the first block from the partition details in point 2
  Press enter to accept the default as the last block.
  Check the partition table by pressing p (to list the partition and confirm)
  Save your new partition table
partprobe
resize2fs /dev/sdX OR xfs_growfs /dev/sdX

## if fdisk does not detect the partitions go with parted -> rm 4(part no) -> mkpart ....