High Availability (was: Re: slave2master replication)

["Mariano Absatz" <openldap@pert.com.ar>]

I'm new to the list (& to ldap), so shout at me in a lower tone if I am 
downright out of tune in here...


El 10 Nov 2000, a las 16:04, Kurt D. Zeilenga escribió:

> By definition, there is no such thing as slave to master
> replication.  When attempting to modify a slave, the
> slave will refer the client to the master (if properly
> configured).  Not all clients will automatically chase
> this referral, but that's yet another matter.
> 
> Kurt
That's what I thought, now, is there a way of providing some kind of HA 
to openldap?

That is, I want to have a couple (or more) servers being able not only to 
answer queries, but I would also like them to be able to accept 
modifications to the tree.

The servers themselves would be topografically together, that is they 
would share an ethernet (or a fast-ethernet).

Is it possible/reasonable/ridiculous putting the .../var/openldap-ldbm in 
a share nfs directory? if so, should I turn off slurpd since the servers 
are actually using the same data? what about caching?

Is there any other obvious (or not) way to do what I want?

TIA

> 
> At 10:04 AM 11/9/00 +0100, Martin Dehn wrote:
> 
> >Hi,
> >
> >well, after reading forth and back through the openldap-software
> >mailing-list archive of this year I gave it up to find a solution to a 
> >problem which is often mentioned.
> >How can the slave-to-master replication be enabled? I did some testing with
> >OpenLDAP2.0.6 (a colleague of mine did the same with OpenLDAP1.2.*). The
> >following are our findings:
> >
> >1) replication from master to slave is working perfectly
> >2) slave is configured with correct updatedn and updateref
> >3) ldapmodify operations on the slave are carried out only for the slave slapd.
> >   No message is going to the master, no error comment, nothing as described
> >   in chapter 10.1 of the most recent "OpenLDAP Administrators Guide".
> >4) Trying some of the advices found in the mailing list, like also setting a
> >   global referral directive in slapd.conf of the slave pointing to the master
> >   does not show the desired result.
> >
> >I suspect that a concluding answer to this problem would be appreciated by a lot of 
> >OpenLDAP users. Getting the answer that currently the slave2master 
> >replica-referral is not working, would also be helpful. 
> >Furthermore, if the problem is described and located in the source code, 
> >maybe we could contribute to a solution.
> >
> >I am looking forward to receiving helpful comments
> >
> >        Martin
> >
> >-- 
> >Dr. Martin Dehn <dehn@id-pro.de> (Consulting)
> >* ID-PRO Deutschland GmbH * G.-Heinemann-Ring 135 * D-81739 München
> >* Tel: +49 (0)89-67 34 61-60 * Fax -70
> >* http://open-for-the-better.com