Flexible multi-master support.

[Gertjan van Wingerde <gwingerde@home.nl>]

Hi,

I've just uploaded a patch to ftp.openldap.org which I would like to have
discussed prior to submitting it via the ITS-system. This patch implements a
more flexible way of doing multi-master setups than the currently implemented,
but disabled at compile-time, symmetric multi-master setup. The patch does the
following 3 things:

	1. It allows the user to configure an identifier for each replica in the
	   slapd.conf file.

	2. It allows the user to configure multiple updatedn DN's in order to
	   separate LDAP replication traffic from each other (e.g. to handle
	   replication traffic coming from one DN (= server) different from LDAP
	   replication traffic coming from an other DN (= server).

	3. It allows the user to configure per updatedn the set of replica's
	    the incoming replication traffic should be replicated to.

The reason for implementing this is twofold:

	1. It allows me to set up an LDAP server tree on one site, which efficiently
	    replicates data across a large farm of LDAP servers.

	2. It allows me to set up a multi-site, geographically distributed, LDAP
	   solution, in which the replication traffic only has to go once over the
	   WAN link between the sites.

The functionality is implemented fully backwards-compatible, i.e. all existing
LDAP configuration still behave as before.

Please let me know what you think of it, whether anything is missing in the
patch and whether you would consider this approach for inclusion into the
mainline OpenLDAP source-tree.

The patch is available under:
		ftp://ftp.openldap.org/incoming/gwingerde-multimaster-support.diff

Best regards,

-- Gertjan