[LU-15625] set_param -P must not be used for root squash

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.16.0, Lustre 2.15.2
• Labels: sec
• Severity: 3
• Assignee: Sebastien Buisson
• Reporter: Sebastien Buisson

Description

Only lctl conf_param must be used to set root squash parameters. If lctl set_param -P is used, the value is set only on server side permanently, and any other value set via conf_param is ignored. Plus this value is not forwarded to client side.

Comments

[Gerrit Updater]

"Oleg Drokin <[e-mail]>" merged in patch https://review.whamcloud.com/47792/
Subject: LU-15625 sec: fix set_param -P for root squash
Project: fs/lustre-release
Branch: b2_15
Current Patch Set:
Commit: 8ea47747c9fcf3ba1d0bca8456f2ad978f8dd2d5

[Peter Jones]

Landed for 2.16

[Gerrit Updater]

"Sebastien Buisson <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/47792
Subject: LU-15625 sec: fix set_param -P for root squash
Project: fs/lustre-release
Branch: b2_15
Current Patch Set: 1
Commit: 6db1730e59e574bd5e6cb5537248eaf9e760322c

[Gerrit Updater]

"Oleg Drokin <[e-mail]>" merged in patch https://review.whamcloud.com/46739/
Subject: LU-15625 sec: fix set_param -P for root squash
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: 7b8449e8f9ed310376a191ec8dfa2f1cb6233377

[Gerrit Updater]

"Sebastien Buisson <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/46739
Subject: LU-15625 sec: fix set_param -P for root squash
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: 9dcb2e477ad58f35b9d63e689350e0fb927a0168

[Sebastien Buisson]

OK, after discussion with Andreas, approach taken in https://review.whamcloud.com/46728 is not the best way to go.

The patch for this problem should consist in fixing set_param -P for root_squash and nosquash_nids parameters, so that this setting is correctly propagated to clients, and we do not end up with clients with inconsistent or no values at all for these parameters.

[Andreas Dilger]

It isn't really clear why "set_param -P" is not working in this case? Is there a different path or parameter name in use on the client compared to the server?

It looks like that is the root of the problem:

# lctl list_param -R "*" | grep squash
llite.myth-ffff90f574676000.nosquash_nids
llite.myth-ffff90f574676000.root_squash
mdt.myth-MDT0000.nosquash_nids
mdt.myth-MDT0000.root_squash
nodemap.default.squash_gid
nodemap.default.squash_uid

It looks like the squash parameter needs to be set like:

# lctl set_param -P *.myth*.root_squash=x:y
# lctl set_param -P *.myth*.nodquash_nids=xxx 

So that it includes the fsname but not the device name, so that it applies on both the client and server.

It would really be better for usability if "set_param -P" just worked properly in this case, since users are very unlikely to read the manual. One option would be for the config llog parsing to detect the case of mdt.*.root_squash and replaced it with llite.* so that it "just worked".

[Gerrit Updater]

"Sebastien Buisson <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/46728
Subject: LU-15625 sec: set_param -P must not be used for root squash
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: fa37f40d246748937f8f0bf459c34b7c72e75c44