[LUDOC-183] Where to run changelog commands.

• Status: Open
• Project: Lustre Documentation
• Type: Improvement
• Priority: Minor
• Reporter: James Nunez (Inactive)
• Assignee: Lustre Manual Triage
• Resolution: Unresolved

Description

There was a conversation on HPDD-discuss recently about where to run certain changelog commands. The manual isn't clear on where certain commands have to be run, i.e. on client only, server only, etc. We need to clarify where changelog commands need to be run.

The following is some of the conversation from the mail list:
Message 1:
In a test Lustre 2.4.0 filesystem we are running into difficulties viewing the changelogs on the mds. Is there something I'm doing wrong here? There are two clients registered, and I can see the current index increment when I perform file creates/unlinks.

Any help would be greatly appreciated!

[root@node-mds1 ~]# lfs changelog lustre-MDT0000 can't find fs root for '(null)': -19 Can't open lustre-MDT0000: -19

Can't start changelog: No such device

[root@node-mds1 ~]# cat /proc/fs/lustre/mdd/lustre-MDT0000/changelog_users
current index: 120819
ID index
cl1 2962
cl2 2962

Message 2:
Does this command need to be run on the client instead of the server? The manual doesn't make it very clear, but some of the examples I have seen show "lfs changelog" running on a system that is not the MDS.

Message 3:
This is correct. You also should add the changelog consumer I'd to your LFS
changelog command.

Message 4:
Ah, that's it. 'lfs changelog lustre-MDT00000 cl1' works from the client.