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Re: (ITS#5354) slapd repeatedly hangs and stops reponding

Oren Laadan wrote:
> Pierangelo Masarati wrote:
>> hyc@symas.com wrote:
>>> Oren Laadan wrote:
>>>>> It shows enough; back-meta is hanging waiting for responses from some other
>>>>> LDAP server. This is a pretty bad configuration; you should not use back-meta
>>>>> (or back-ldap) to redirect queries back into the same slapd. You should use
>>>>> back-relay instead.
>>>> I'm not quite sure why having the server query itself is such a bad idea.
>>>> Can you please explain ?
>>> Any request then occupies a minimum of two slapd threads - one for back-meta
>>> itself, and one for the extra inbound query. If you misconfigure the meta URIs
>>> then you get into an infinite loop, which consumes all of the available slapd
>>> threads.
>> Let me add that, moreover, any request is re-encoded as an LDAP request,
>> sent to itself, re-decoded and re-processed by slapd.  Back-relay
>> directly relies the original, decoded request to another database,
>> within the same thread.  So it saves at least 3 resource-consuming steps-
> Ok, I see the rational. So I guess my question is whether back-relay gives
> the same functionality like ldap-meta (that is, merging the two databases,
> the remote one and the local one) except better with respect to a local
> database ?  and if so, then how would I set it up for this ?
> I looked at "subordinate" directive but I'm not sure it helps, since as
> far as I could tell it can join two disjoint subtrees into seemingly one
> big database. However, what I need is to add local (new) entries (not
> only modify attributes) to an existing database.

This discussion has wandered off of potential bugs and into regular software 
usage. You should pick this up again on the -software mailing list. This ITS 
will be closed.
   -- Howard Chu
   Chief Architect, Symas Corp.  http://www.symas.com
   Director, Highland Sun        http://highlandsun.com/hyc/
   Chief Architect, OpenLDAP     http://www.openldap.org/project/