Hi,

On a customer site we have a file system originally formatted with Lustre 2.1. On this file system several changelog users were registered, and changelogs were working fine.

Then this file system was upgraded to 2.4. But it broke changelogs usage, as no changelog user is registered anymore. Moreover, former changelog records are unreachable.

As noted by Aurelien Degremont in his email (https://lists.01.org/pipermail/hpdd-discuss/2014-January/000713.html), it seems to be due to changes in the llog interface in 2.4 (changelog_catalog and changelog_users file are now in root MDT directory, changelog_catalogs do not point to other files in OBJECTS/ directory anymore, etc).

We would need a method to migrate the 'changelogs configuration' from 2.1 to 2.4.

Thanks,
Sebastien.