Shrinking ext3 partition

*** Make sure you have a back up prior to proceeding. ***

1. Boot into rescue mode.
   
2. Unmount partition if mounted and check disk:
   
   umount /dev/sda1
e2fsck -vn /dev/sda1
3. Remove journaling from ext3 partition and revert to ext2, as resize2fs does not work on ext3 partition. (Note: This step should not be necessary in recent kernels.)
   
   tune2fs -O ^has_journal /dev/sda1
4. Force check the partition:
   
   e2fsck -vf /dev/sda1
5. Resize the partition making sure that you don't shrink it lesser than the disk space currently used else you may lose data.
   
   resize2fs /dev/sda1 6000M
6. Make a note of the blocks and block size. You can also run:
   
   dumpe2fs /dev/sda1
7. Delete /dev/sda1 partition and create a smaller one with fdisk:
   
   fdisk /dev/sda
8. Recreate the partition /dev/sda1 with the starting point at the default location and the ending point at number of blocks from the resize2fs output (1536000) multiplied by the size of a block (4K). So, the end point would be 1536000 * 4 = 6144000K.
   
9. Run partprobe and resize2fs utility with no size arguments:
   
   partprobe /dev/sda
resize2fs /dev/sda1

   Note: If resize2fs errors out, you may need to further increase the block size by a small percentage (3 to 5%).

10. Run a disk check for the final time before restoring the journal.
    
    e2fsck -vn /dev/sda1
tune2fs -j /dev/sda1
11. Reboot and check everything in file-system is intact.