Re: OpenLDAP 2.0.13 released

[Pierangelo Masarati <masarati@aero.polimi.it>]

Sovan_Shatpathy@satyam-infoway.com wrote:
> 
> Hi,
>         Here we are looking at a scenario where there will be around 20 million
> records which we will be storing in the ldbm database. Also  we are going in for
> selective replication across some twenty slave servers.( each at diff physical
> location)
> 
> Currently we are using the back-meta concept of Openldap (which is not a release
> version) where we have multiple instances of ldbm in the master server and hence
> also multiple slurpd processes running in the back ground. But then if we go in
> for  any release  version of openldap be it 2.0.13 or 14  then i believe we need
> to go in for a single ldbm databse in the master  instead of having multiple
> ldbm 's .
> 
> Now my question here is two fold :
> 
> 1. Which is the better way to do  a search in the master ..is it by having
> multiple ldbm's ( as we have currently with the back meta concept ) or is it by
> having one single ldbm  database .

On one side, back-meta adds an extra (tcpip unless you use ldapi:// URIs
for
local targets) layer to the search; on another, it allows to split large 
databases into smaller ones, so point searches (especially if the base
allows 
to resolve the correct target only) could be a little faster.

> 
> Where will be the speed of authentication  be faster ?? We  need an answer for
> this because we are  looking at a record which will exceed more than 20 million
> in the near future...

again, see the above point. If auth is directly performed with a dn,
back-meta
should not be worse than back-ldbm; if you need to fetch the dn based on
some
user id with a full naming context-wide search, then it might be a
littel slower.
However I never tried a +20M entry db, my experience is limited to 100K
ones.

> 
> 2. Which is the better way of doing  replication ? Is it by having a single
> slurpd process doing selective replication across 20 slave servers(as in version
> 2.0.14)  or is it by having multiple slurpd processes .

I don't see so many differences in the two solutions from this
standpoint.

Remember that back-meta should be seen as a means to nail together
etherogeneous 
servers, not as a solution from scratch. I remember you started using it
because 
of the subtree replication issue, which is now fixed since 2.0.13. I'd
maintain 
it if the single servers can be used by themselves. I mean: if each
server
serves a subdomain (don't take it literally) and subdomain-related
operations
can be performed directly on the appropriate server, while access thru
back-meta 
is required only by domain-wide operations, then I'd stay with the
back-meta
solution. Otherwise, if all the operations potentially are domain-wide,
I'd
use the back-ldbm solution with partial replication. It sounds less
error-prone
because the back-ldbm allows much more consistency checks on operations
than 
back-meta can do. Moreover, reducing the number of databases and the
amount 
of configuration makes maintenance easier.

> 
> 3. What is the support we may have for back meta in near future? In the sense
> that we  wanted to know as  to if there are any plans of coming out with a
> release version of back meta in the immediate future. This can then help us  to
> decide with what should we go in for production set up.( i.e back meta or
> version 2.0.14)

I don't think there's any schedule about that. It's an extra feature 
with limited potential use. At present I think it's only slightly less 
mature than back-ldap, from which it descends, so it could be released.
It depends on the demand: the more people need it, the sooner it will 
make into release. It is currently developed, it and used in production
environment in my organization. However its use is limited in nailing
together legacy OpenLDAP, Lotus Notes and Active Directory services 
for address book and mail routing purposes (many different companies
are merging and maintain independent directories for their stuff).

Pierangelo.


-- 
Dr. Pierangelo Masarati               | voice: +39 02 2399 8309
Dip. Ing. Aerospaziale                | fax:   +39 02 2399 8334
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