Ubuntu – How to mount a Truecrypt volume with special options

ext4mounttruecrypt

I would like to mount an ext4 truecrypt drive with --fs-options but it doesn't work. Also I created a FAT partition and the following command is working. What is the alternative command if my partition is ext3/ext4?

sudo truecrypt --mount /media/vulturus_data/test3 /media/true  --fs-options="users,uid=115,gid=123,fmask=0113,dmask=0002"

Best Answer

Those filesystem options are available for FAT because FAT does not support file permissions. Ext2/ext3/ext4 filesystems on the other hand do support file permissions. After mounting the container on /media/true:

  • Change ownership and group membership (corresponds to uid=115,gid=123):

    sudo chown -R 115:123 /media/true

  • fmask=0113 removes the executable bit from all files and write bit from the others. This is the default, so you should not need to change it. Anyway, the command to do so is:

    sudo find /media/true -type f -exec chmod a-x,o-w {} \;

  • dmask=0002 is supposed to remove the write bit from directories for the world. This bit is usually not set. To remove it in case it is set:

    sudo find /media/true -type d -exec chmod o-w {} \;
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