Introduction

This howto will show you how to upgrade from ext3 file system to ext4 file sytem

Please be aware that following this instructions may destroy all your data, so you are really encouraged to back up all your data before continuing.

Also, before doing any conversion, be sure you are really going to notice some noticeable improvements.

ext4 according to wikipedia is:

The ext4 or fourth extended filesystem is a journaling file system for Linux, developed as the successor to ext3.

And is was created…

…as a series of backward compatible extensions to ext3 meant to extend storage limits and add other performance improvements. However, other Linux kernel developers opposed accepting extensions to ext3 for stability reasons, and proposed to fork the source code of ext3, rename it as ext4, and do all the development there, without affecting the current ext3 users. This proposal was accepted, and on 28 June 2006, Theodore Ts’o, the ext3 maintainer, announced the new plan of development for ext4.

If you are interested, you can read some ext3 vs ext4 comparison.

Well, now that you have decided that ext4 is for you, you can use this guide to switch from ext3 to ext4.

Really important note: Backup before you start, if this fail, you may loss all your data. So you have been warned

Transforming from ext3 to ext4

This assumes, you have your disk on /dev/sdc1 your configuration may change.

Also, if you want to convert your root partition, you will have to boot with another Linux, you will not be able to convert your running root partition.

sudo tune2fs -O extents,uninit_bg,dir_index /dev/sdc1

Remember to change /dev/scd1 to fit your needs.

sudo fsck -pf /dev/sdc1

Once again remember to change /dev/sdc1 to fit your needs.

Now you can mount your new system as ext4

sudo mount -t ext4 /dev/sdc1 /mnt

And you will have to change in /etc/fstab file:

Where it said ext3 now should say ext4 for the /dev/sdc1 partition.

Before:

/dev/sda1   /    ext3   defaults         1   1

After

/dev/sdc1  /     ext4   defaults          1   1

Your options may differ.