[LU-28] Ability for client to mount subdirectories of a Lustre filesystem

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.9.0
• Affects Version/s: Lustre 2.0.0
• Labels: patch
• Severity: 3
• Bugzilla ID: 15,267

Epic

metadata mount

• Assignee: Wang Shilong (Inactive)
• Reporter: Lai Siyao

Description

In kicking around some ideas for the use of Lustre as a replacement for NFS user directories (home and application areas), the thought of being able to export/mount a subdirectory of a Lustre LOV came up.

Issue Links

• has to be finished together with: LUDOC-319 Add subdirectory mount feature to manual
• is related to: LU-5989 add subdirectory mounting support for lustre

Comments

[Joseph Gmitter (Inactive)]

The patch has landed to master for 2.9.0

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch http://review.whamcloud.com/5007/
Subject: LU-28 fileset: add fileset mount support
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: 9bd3e64b817ccbbf9760864b84908b87e13ebfe8

[Lai Siyao]

As Andreas suggested above, this feature should support mount with fileset name instead of "traverse directory on client" hack. This is not a minor change, I'll update it later.

[Peter Jones]

Scott

Thanks for drawing attention to this.

Lai

Kit has moved on to a new job. Could you please refresh the patch on his behalf?

Thanks

Peter

[Scott Nolin (Inactive)]

Has this patch been held up just due to the tab/space formatting issues since last January?

We are looking at working around this with bind mounts, and I ran across this patch.

Scott

[Andreas Dilger]

What would also be very useful here for future expansion is to enhance the MDS_GETSTATUS RPC to accept a fileset name, currently always "ROOT", so that this handling can be done by the MDS in the future and the "traverse directory on client" hack can be avoided. That would allow completely independent filesets to be handled by different subtrees on the same MDT. For the initial implementation, the MDT would just check for "ROOT" (if it is sent), and return -ENODEV if it is something else, but it would at least get clients ready for the next step.

[Kit Westneat (Inactive)]

Great, thanks

[Peter Jones]

Kit

No further action is needed - the patch is already in the queue for landing consideration

Peter

[Kit Westneat (Inactive)]

Thanks for the review. I'm still new to Gerrit, is there someone I should add for +2?

[Kit Westneat (Inactive)]

I rebased it on master, it's here: http://review.whamcloud.com/#change,5007