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Re: what databases are to be replicated for a slave?

--On Tuesday, December 29, 2015 12:48 PM +0400 Jephte Clain <jephte.clain@univ-reunion.fr> wrote:

No.  Replicas do not accept writes.  Replicas do not have a master
configuration for cn=config.  Replica's do not have server IDs.
ok I guess I understand. this is the reason why I usually call them
"slaves", not replicas (but I messed things up and called them replicas
this time ^^)
I also have replicas that only replicate data (or a subset of data) for
some services

No. The terms replica and slave are interchangeable. As are master and provider. Given the very negative connotations of the concept of masters and slaves, the preferred terms are "provider" instead of "master" and "replica" instead of "slaves".

the slaves are there in case of catastrophic failure of both masters (we
had one of these failure for another service due to a problem with the
shared storage. No one want to have this kind of emergency...)
If the master(s) crash, I just have to choose a slave as the new master,
slapcat the cn=config database, update the provider address, slapadd the
updated config, and update the loadbalancer settings. this is a bit of
work but at least we can restore service in a (relatively) small amount
of time.

If they accept writes, they are not slaves/replicas. If you are replicating cn=config across all the systems, then they must all be masters. Your general description above sounds like you do not correctly understand how MMR functions.

Accesslog is unique to a given master.
Ok that's what I wanted to know for sure

Shouldn't the doc stat this clearly?

Please file an ITS noting the docs should be updated on this point.

Thanks a lot for the clarification. In case you come to the reunion
island someday, I owe you a beer!




Quanah Gibson-Mount
Platform Architect
Zimbra, Inc.
Zimbra ::  the leader in open source messaging and collaboration