resize2fs

Resize an ext2, ext3 or ext4 filesystem. Does not resize the underlying partition. The filesystem may have to be unmounted first, read the man page for more details. More information: https://manned.org/resize2fs.

• Automatically resize a filesystem:
  resize2fs {{/dev/sdXN}}
• Resize the filesystem to a size of 40G, displaying a progress bar:
  resize2fs -p {{/dev/sdXN}} {{40G}}
• Shrink the filesystem to its minimum possible size:
  resize2fs -M {{/dev/sdXN}}