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With Ubuntu 9.04 (jaunty) the new filesystem ext4 is part of the platform. The Truecrypt GUI (6.1a) does not allow to select for ext4 as filesystem. The challenge was to create the ext4 filesystem using as much of the GUI and do not need to bother about command line options. I’m using a complete device for the Truecrypt container, but the solution should work on volumes and file containers as well.

To do so I’ve taken the following steps to create the Truecrypt container without a filesystem:

1. Start the Truecrypt GUI


Truecrypt main panel

2. Click on Create volume
   

   Volume Creation Wizard

3. Select Create a volume within a partition/drive
4. On the next page select the Volume Type (I opt for the Standard volume)
5. On the next page Select the Device
   By doing so, Truecrypt shows the following message.


Confirm using volume

6. Click Yes on using a device
7. Enter your password in the popup to allow root privileges for Truecrypt
8. Select the Encryption Algorithm (I opt for the defaults)
9. On the Volume Password set your password and/or keyfiles (I opt for a key file only at this point)
10. On the next page (Large files) I selected larger then 4GB as I have several VMWare/VirtualBox images that are larger then 4GB.
11. On the next page (Format Options) select None as ext4 is not in the list
12. On the next page (Volume Format) move the mouse around before clicking Format
13. Click Yes on the confirmation button to format the volume
14. For my 320GB drive the format will take about 80 minutes
15. So time for a break…
16. On the Volume Created page click Exit

Now the ext4 filesystem can be added. I used the Truecrypt GUI for the first few steps:

1. On the main panel of Truecrypt click Select Device and select the truecrypt drive
2. Click Mount on the main panel
3. Expand the section with options
4. Check the Filesystem: “Do not mount” option as there is no filesystem yet
   

   Truecrypt mount options

   Enter the password and/or add the keyfiles and click OK

5. Now the device is mounted so the filesystem can be created
   

   Mounted Truecrypt device

From here it is the command line interface to get a filesystem installed, the steps:

1. Goto to a terminal window
2. Type ls /dev/mapper , the output should show truecrypt1
3. Create the filesystem with sudo mkfs.ext4 /dev/mapper/truecrypt1 which should not take that long

Note that you must not make the filesystem on the underlaying device like /dev/sdb as it removes the Truecrypt container.

Go back to the Truecrypt GUI and perform the last steps to complete and verify are:

1. Dismount the encrypted device
2. Click Select Device and locate the device
3. Click Mount and enter the password and/or key file locations, and don’t change the Options, and click OK
4. The encrypted device will be mounted by default to /media/truecrypt1