Use the following command with the block device corresponding to the root file system:

# tune2fs -j device

The command adds an ext3 journal to the file system as the file /.journal.

Run the mount command to determine the device that is currently mounted as the root file system.

In the following example, the root file system corresponds to the disk partition /dev/sda2:

# mount
/dev/sda2 on / type ext2 (rw)

Shut down the system.

Boot the system from an Oracle Linux boot CD, DVD or ISO. You can download the ISO from https://edelivery.oracle.com/linux.

From the installation menu, select Rescue Installed System. When prompted, choose a language and keyboard, select Local CD/DVD as the installation media, select No to bypass starting the network interface, and select Skip to bypass selecting a rescue environment.

Select Start shell to obtain a bash shell prompt (bash-4.1#) at the bottom of the screen.

If the existing root file system is configured as an LVM volume, use the following command to start the volume group (for example, vg_host01):

bash-4.1# lvchange -ay vg_host01

Use fsck.ext3 to check the file system.

bash-4.1# fsck.ext3 -f device

where device is the root file system device (for example, /dev/sda2).

The command moves the .journal file to the journal inode.

Create a mount point (/mnt1) and mount the converted root file system on it.

bash-4.1# mkdir /mnt1
bash-4.1# mount -t ext3 device /mnt1

Use the vi command to edit /mnt1/etc/fstab, and change the file system type of the root file system to ext3, for example:

/dev/sda2        /       ext3    defaults  1 1

Create the file .autorelabel in the root of the mounted file system.

bash-4.1# touch /mnt1/.autorelabel

The presence of the .autorelabel file in / instructs SELinux to recreate the security attributes of all files on the file system.

Unmount the converted root file system.

bash-4.1# umount /mnt1

Remove the boot CD, DVD, or ISO, and reboot the system.