Hi there

Sorry for the long post however I aim to provide as much information as possible to help pinpoint the issue. Also sorry for any wrong wording as I am still a bit overwhelmed with OpenLDAP and struggle to understand everything I need.

From my predecessor I inherited an OpenLDAP 2.4.x cluster running on RHEL 7. My job is to migrate this cluster to OpenLDAP 2.6.x on RHEL 8. The cluster consists of two provider and four consumer servers. The old cluster was based on self-compiled original OpenLDAP binaries. For the new cluster I am using the LTB version of OpenLDAP, currently with version 2.6.8. I also switched from HDB to MDB with the new cluster and am using Let's Encrypt instead of DigiCert certificates and upped the TLS version from 1.0 to 1.2. And for the default password hashing algorhythm I switched from SSHA to ARGON2. So there are lots of changes that might potentially influence the meta databases though I did not see anything that suggests this.

The synchronisation of the normal databases between the provider servers and to the consumer servers is working fine. My problem is with the meta databases I try to build using slapd-meta. They are only needed on the consumer servers. Unfortunately the meta databases do not seem to be created or are not working as expected. On the old cluster I can ldapsearch in the meta databases and they show up as trees when connecting with Apache Directory Studio. On the new cluster I am setting up I don't see those meta trees in Apache Directory Studio and ldapsearches don't return any results. Furthermore slapcat on those databases returns the message "slapcat: database doesn't support necessary operations."

The meta trees don't query external servers but suffixmassage locally present sub-trees. From what I've read this could also be accomplished with slapd-relay but the man page states that it is experimental. That is why I am trying the same way my predecessor did using slapd-meta.

I temporarily set the loglevel to 4094 but even then did not see any hint on what goes wrong with those meta databases. By the way, when I do set the loglevel so high I can no longer connect using Apache Directory Studio, but that is not the issue I'm concerned about.

Neither the documentation, nor the slapd-meta man page, nor the very few tutorials/stackexchange-posts/mailinglist-posts I found online about meta-back helped me in solving this issue. That is why I hope someone on this mailinglist can spot an issue in my configuration. Or point me to other resources/tutorials or share some debugging advice. For the purpose of sharing the configuration I omitted all the schemata and some of the ACLs. Also I removed the linebreaks so what belongs together is all on one line. Lastly I redacted any sensitive information. It is attached as a text/ldif file.

Thanks a lot in advance and let me know if I need to share further information such as log entries etc.

Best regards, Cyril