tune2fs and luks

[Bruno Wolff III]

On Mon, Jul 19, 2010 at 15:17:36 +0100,
  Frank Murphy <frankly3d at gmail.com> wrote:
> Can someone set me right with tune2fs and luks encrypted drives.
> Have googled but cannot find an example.
> Please don't say man luks.

You need to have it luks opened first. You need to reference the device
by the device mapper name. For example:
tune2fs -l /dev/mapper/luks-9cfcdd2a-d2ff-4c30-818c-344764c7cc21