Ext4 – How to Disable Journaling in Ubuntu 14.04

ext4shredding

I installed Xubuntu (sometimes running Cinnamon, but I digress) and would like to disable journaling in order to make file-shredding the ext4 system partition more effective (non-system/app data is on an NTFS partition). How can this be accomplished?

Best Answer

  • Whatever you do you, make a backup before you play with filesystems!
  • Check the manpages ( man tune2fs ) before using this!
  • This only works on ext filesystems!

To disable journaling you can use (where XN points to your partition letter and digit):

tune2fs -O ^has_journal /dev/sdXN

From the man page:

tune2fs - adjust tunable filesystem parameters on ext2/ext3/ext4 filesystems

Option: -O [^]feature[,...]

Set or clear the indicated filesystem features (options) in the filesystem. More than one filesystem feature can be cleared or set by separating features with commas. Filesystem features prefixed with a caret character ('^') will be cleared in the filesystem's superblock; filesystem features without a prefix character or prefixed with a plus character ('+') will be added to the filesystem.

...

has_journal

Use a journal to ensure filesystem consistency even across unclean shutdowns. Setting the filesystem feature is equivalent to using the -j option.

You might also need the ...

Option: -f

Force the tune2fs operation to complete even in the face of errors. This option is useful when removing the has_journal filesystem feature from a filesystem which has an external journal (or is corrupted such that it appears to have an external journal), but that external journal is not available.

WARNING: Removing an external journal from a filesystem which was not cleanly unmounted without first replaying the external journal can result in severe data loss and filesystem corruption.


The filesystem needs to be either unmounted or in read-only mode. From the grub prompt: "advanced options" -> "recovery mode" -> "Drop to a root shell prompt" or use a Live DVD.