[lustre-discuss] Lustre on native ZFS encryption

[Mohr Jr, Richard Frank (Rick Mohr)]

> On May 2, 2018, at 10:37 AM, Mohr Jr, Richard Frank (Rick Mohr) <rmohr at utk.edu> wrote:
> 
> 
>> On May 2, 2018, at 9:59 AM, Mark Miller <mmill116 at jhu.edu> wrote:
>> 
>> Since I have the Lustre source code, I can start looking through it to see if I can find where the Lustre mount system call may be getting hung up.  I have no idea... but it feels like the Lustre mount may be trying to read something from the zfs filesystem “under the hood”, and it’s getting the result back in its encrypted state.  We always have LUKS encryption to fall back to.
> 
> That could very likely be the case.  I know that with ldiskfs, when you mount a lustre target, there is info about mount options stored in the file system that gets retrieved with one of the e2fsprogs tools (maybe debugfs) which is then used when performing the actual mount.  So I could easily see something trying to query a ZFS attribute to retrieve similar information before doing the mount.

I just verified that lustre/utils/mount_utils_ldiskfs.c makes a call to debugfs.  You will probably want to look at lustre/utils/mount_utils_zfs.c for something similar.

--
Rick Mohr
Senior HPC System Administrator
National Institute for Computational Sciences
http://www.nics.tennessee.edu