[LUDOC-377] Lustre Manual Bug Report: 25.2.2. Enabling and Tuning Root Squash

• Type: Bug
• Resolution: Fixed
• Priority: Minor

Epic/Theme

Lustre-2.8.0

• Severity: 3

Epic

server

• Assignee: Joseph Gmitter (Inactive)
• Reporter: Faye Gibbins (Inactive)

Description

Hi,

I think I’ve found a bug in the manual: https://build.hpdd.intel.com/job/lustre-manual/lastSuccessfulBuild/artifact/lustre_manual.xhtml#dbdoclet.50438221_48757 I’ve included it below in case this is the correct place to report it. If not please let me know and I’ll submit it elsewhere.

In section 25.2.2. Enabling and Tuning Root Squash, the bit that says:

Root squash parameters can also be changed with the lctl conf_param command. For example:

mgs# lctl conf_param testfs.mdt.root_squash="1000:101"
mgs# lctl conf_param testfs.mdt.nosquash_nids="*@tcp"

Should be IMHO:

Root squash parameters can also be changed with the lctl conf_param command. For example:

mgs# lctl conf_param mdt.testfs-MDT0000.root_squash="1000:101"
mgs# lctl conf_param mdt.testfs-MDT0000.nosquash_nids="*@tcp"

Here is an example of me using my version compared to the documentation version using Lustre 2.8 on RHEL 7:

0 edi-vf-1-5:audiodb-MDT0000# lctl get_param mdt.audiodb-MDT0000.root_squash
mdt.audiodb-MDT0000.root_squash=0:0
0 edi-vf-1-5:audiodb-MDT0000# lctl set_param mdt.audiodb-MDT0000.root_squash="0:1"
mdt.audiodb-MDT0000.root_squash=0:1
0 edi-vf-1-5:audiodb-MDT0000# lctl get_param mdt.audiodb-MDT0000.root_squash
mdt.audiodb-MDT0000.root_squash=0:1
0 edi-vf-1-5:audiodb-MDT0000# lctl set_param mdt.audiodb-MDT0000.root_squash="0:0"
mdt.audiodb-MDT0000.root_squash=0:0
# Using the documented version.
0 edi-vf-1-5:audiodb-MDT0000# lctl set_param audiodb.mdt.root_squash="0:1"
error: set_param: param_path 'audiodb/mdt/root_squash': No such file or directory
0 edi-vf-1-5:audiodb-MDT0000#

Yours
Faye Gibbins

Comments

[Joseph Gmitter (Inactive)]

Patch was landed a few months ago.

[Gerrit Updater]

Andreas Dilger ([e-mail]) merged in patch https://review.whamcloud.com/27954/
Subject: LUDOC-377 misc: cleanup of root squash settings
Project: doc/manual
Branch: master
Current Patch Set:
Commit: 177f5c0ca6e004c8db5df8679c64f7491a6ce928

[Gerrit Updater]

Joseph Gmitter ([e-mail]) uploaded a new patch: https://review.whamcloud.com/27954
Subject: LUDOC-377 misc: cleanup of root squash settings
Project: doc/manual
Branch: master
Current Patch Set: 1
Commit: f67b3e17e907cd9ea3415c9b3ff66fad70511e3b

[Joseph Gmitter (Inactive)]

There are two ways to setting root_squash: conf_param and set_param.

For conf_param, the documetation is correct on how to permanently set it (must be run on the mgs):

[root@rh73-mds1 ~]# lctl conf_param testfs.mdt.root_squash="1:0"
[ 5260.733978] Lustre: Setting parameter testfs-MDT0000.mdt.root_squash in log testfs-MDT0000
[root@rh73-mds1 ~]# [ 5269.090417] Lustre: testfs-MDT0000: root_squash is set to 1:0

To retrieve the setting, the documentation is lacking. From the mgs, it should be:

[root@rh73-mds1 ~]# lctl get_param mdt.*.root_squash
mdt.testfs-MDT0000.root_squash=1:0

As you noted, you can also set it temporarily with set_param (or permanent with set_param -P). This is not documented in the manual and the syntax you noted is correct:

[root@rh73-mds1 ~]# lctl set_param mdt.testfs-MDT0000.root_squash="1:0"
[ 5189.989945] Lustre: testfs-MDT0000: root_squash is set to 1:0
mdt.testfs-MDT0000.root_squash=1:0
[root@rh73-mds1 ~]# lctl get_param mdt.*.root_squash
mdt.testfs-MDT0000.root_squash=1:0

[Faye Gibbins (Inactive)]

I might be wrong but maybe conf_param should be set_param?