resize2fs is a command that allows you to resize an ext2 filesystem or an ext3 filesystem. You typically do this when you find out that having separate partitions on your hard disk is only hindering. You cannot resize a mounted ext2 filesystem. The linux 2.6++ kernel supports on-line resizing of mounted ext3 filesystems.
To unmount your / filesystem, best restart your computer from a live CD.
resize2fs [ -fFpPM ] [ -d debug-flags ] [ -S RAID-stride ] device [s size ]
Note that older versions do not support all options.
To resize a mounted lvm filesystem, unmount it, check the filesystem, resize the filesystem to its minimimum size (-M option), reduce the number of extents and remount
umount /dev/myGroup/myVol e2fsck -f /dev/myGroup/myVol resize2fs -M /dev/myGroup/myVol lvreduce /dev/myGroup/myVol mount /dev/myGroup/myVol