Since the person who wrote the MMR functionality notes it is broken, I'd suggest you consider it broken. Just because it has worked "so far" for you does not mean it will continue to work. You may want to spend some time reading up on exactly who "Howard Chu" is, as well.
Originally Posted by strikermdd
I would note that using cn=config in no way precludes using MMR, since cn=config is the preferred mechanism for configuring OpenLDAP, and will in the future be the only supported method for configuring OpenLDAP. The cn=config database is accessed by using the hard-coded cn=config DN, and you can find the password for it by looking at the ldap_root_password localconfig key.
I would note that setting up Zimbra to use MMR is not supported, and may have unforseen consequences.
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