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

[ando@sys-net.it]

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-

p.



Ing. Pierangelo Masarati
OpenLDAP Core Team

SysNet s.r.l.
via Dossi, 8 - 27100 Pavia - ITALIA
http://www.sys-net.it
---------------------------------------
Office:  +39 02 23998309
Mobile:  +39 333 4963172
Email:   pierangelo.masarati@sys-net.it
---------------------------------------